Clinical Outcomes and Return-to-Sport Rates following Fragment Fixation Using Hydroxyapatite/Poly-L-Lactate Acid Threaded Pins for Knee Osteochondritis Dissecans: A Case Series.

Osteochondritis dissecans (OCD) of the knee is an uncommon injury in young active patients. There is currently a lack of knowledge regarding clinical outcomes and return-to-sport rates after fragment fixation surgery using hydroxy appetite poly-L-lactic acid (HA/PLLA) threaded pins for knee OCD among athletes. Our purpose was to investigate the clinical outcomes and return-to-sport rates following osteochondral fragment fixation using HA/PLLA pins for the treatment of knee OCD lesions among athletes. A total of 45 patients were retrospectively reviewed. In total, 31 patients were excluded, and 14 patients were included. Pre- and postoperative patient-reported outcome scores (PROSs), including the International Knee Documentation Committee (IKDC) score and Knee Injury and Osteoarthritis Outcome Scale (KOOS), were compared. In addition, patients were categorized into four groups according to postoperative sports status: higher, same, lower than preinjury, or unable to return to sports. The mean age was 14.4 years (SD 1.67). All patients were male. All PROSs significantly improved at 6, 12, and 24 months postsurgery compared to presurgery. 50% of the patients returned to sports at the same or higher level after surgery. Fragment fixation using HA/PLLA pins leads to favorable clinical outcome scores and high return-to-sport rates in the treatment of athletes with knee OCD.

Biomechanical Comparison Between Double-Row Repair and Soft Tissue Tenodesis for Treatment of Proximal Rectus Femoris Avulsions.

Background: Some patients with proximal rectus femoris (PRF) avulsions require surgical treatment after failed nonoperative treatment. There is no consensus on the superiority of suture anchor repair with the suture-bridge repair (SBR) technique versus tenodesis repair (TR) for PRF avulsions. Purpose: To compare the failure load and elongation at failure between SBR and TR and to compare the stiffness of these 2 repair techniques versus the native state. Study Design: Controlled laboratory study. Methods: Seven pairs of human cadaveric hemipelvises were dissected to the PRF and sartorius origins. Each specimen underwent preconditioning followed by a distraction test to determine the stiffness of the native specimen. One specimen of each pair received one of the repair methods (SBR or TR), while the other specimen in the pair received the other repair technique. After repair, each specimen underwent preconditioning followed by a pull to failure. The failure load, elongation at failure, stiffness, mode of failure, and stiffness as a percentage of the native state were determined for each repair. Results: The SBR group exhibited a stronger failure load (223 ± 51 N vs 153 ± 32 N for the TR group; P = .0116) and significantly higher stiffness as a percentage from the native state (70.4% ± 19% vs 33.8% ± 15.5% for the TR group; P = .0085). While the stiffness of the repair state in the SBR group (41.5 ± 9.4 N/mm) was not significantly different from that of the native state (66.2 ± 36 N/mm), the stiffness of the repair state in the TR group (20.3 ± 7.5 N/mm) was significantly lower compared with that of the native state (65.4 ± 22.1 N/mm; P < .001) and repair state in the SBR group (41.5 ± 9.4 N/mm; P = .02). The SBR group primarily failed at the repair site (71%), and the TR group primarily failed at the suture-sartorius interface (43%) and at the muscle (29%). Conclusion: SBR and TR specimens were significantly weaker than the native tendon. The stiffness of the SBR was equivalent to that of the native tendon, while TR was significantly less stiff than the native tendon. The SBR was superior to TR in terms of failure load, stiffness, and percentage stiffness from the native state. Clinical Relevance: SBR may be a better surgical option than TR to optimize failure load and stiffness for PRF avulsions.

Biomechanical Comparison of Proximal Hamstring Reconstruction Using Distal Hamstring Graft Versus Fascia Lata Graft for Treatment of Chronic Hamstring Injury.

BACKGROUND: Surgical reconstruction using autografts is often required in treating chronic proximal hamstring injuries where the hamstring has retracted >5 cm. There is a paucity of evidence that evaluates reconstructive procedures using the 2 most popular autografts, distal hamstring and fascia lata. PURPOSE: To (1) compare failure load and elongation at failure between the proximal hamstring tendon reconstruction with distal hamstring and fascia lata grafts and (2) compare the stiffness between these reconstructions and the native state. STUDY DESIGN: Controlled laboratory study. METHODS: Seven pairs of human cadaveric hemipelvises (mean age, 60.4 ± 5.0 years; 6 male, 1 female) with no evidence of previous injury or abnormality were dissected to the proximal hamstring origin. Through use of a dynamic tensile testing system, each specimen underwent preconditioning followed by a distraction test to determine the native specimen stiffness. Each pair of specimens was assigned to undergo proximal hamstring reconstruction with distal hamstring and reconstruction with fascia lata. Each specimen then underwent preconditioning followed by pull to failure. The failure load, elongation at failure, mode of failure, and stiffness were determined for each repair. RESULTS: The distal hamstring group exhibited a greater failure load (mean, 334 ± 108 N; P = .031) and higher stiffness (mean, 47.6 ± 16.0 N/mm; P = .009) compared with the fascia lata group (mean, 179 ± 78 N and 23.0 ± 11.2 N/mm, respectively). Although the stiffness of the repair state in the distal hamstring group (mean, 61.4 ± 13.4 N/mm) was not significantly different from that of the native state (mean, 47.6 ± 16.0 N/mm), the stiffness of the repair state in the fascia lata group (mean, 23.0 ± 11.2 N/mm) was significantly lower than that of the native state (mean, 60.1 ± 17.7 N/mm) (P < .0001). The elongation at failure of the distal hamstring graft group (mean, 33.0 ± 6.6 mm) was not significantly different from that of the fascia lata graft group (mean, 29.2 ± 14.9 mm) (P = .58). The most common modes of failure for the distal hamstring group (29% each) were at the repair site, at the graft-muscle interface, and at the muscle, while the most common modes of failure for the fascia lata graft were at the tendon-graft interface. CONCLUSION: The distal hamstring group achieved higher failure load and stiffness than the fascia lata group, and stiffness of the distal hamstring group was not significantly different from that of the native tendon. Elongation at failure was not different between repair techniques. Although distal hamstring graft failure predominantly occurred in 3 distinct locations, failure of the fascia lata repair occurred predominantly at the tendon-graft interface. These cadaveric results suggest that it may be more clinically appropriate to use distal hamstring versus fascia lata for proximal hamstring reconstruction. CLINICAL RELEVANCE: Our time-zero study suggests that the proximal hamstring reconstruction with distal hamstring could be the preferred surgical treatment for chronic hamstring injury over reconstruction with fascia lata. The failure load of reconstruction with distal hamstring was inferior to that of primary suture anchor, suggesting that rehabilitation after reconstruction should not be more aggressive than the standard postoperative rehabilitation protocol for acute repair.

Arthroscopic Hip Capsular Repair Improves Patient-Reported Outcome Measures and Is Associated With a Decreased Risk of Revision Surgery and Conversion to Total Hip Arthroplasty.

Purpose: To perform a systematic review to assess the effect of capsular repair compared with nonrepair on patient-reported outcome measures (PROMs) and conversion to total hip arthroplasty (THA) after hip arthroscopy in patients with femoroacetabular impingement syndrome. Methods: We initially searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, and PubMed databases, as well as ongoing clinical trials (https://clinicaltrials.gov), on December 15, 2022. The eligibility criteria were randomized controlled trials (Level Ⅰ) and prospective comparative studies (Level II) of patients who underwent capsular repair and nonrepair via hip arthroscopy with a minimum follow-up period of 2 years. We registered this protocol a priori on PROSPERO (identification No. CRD42021239306). We assessed the risk of bias using the Methodological Index for Non-randomized Studies (MINORS) appraisal tool. Results: This review included 5 studies with a total of 639 patients (270 with capsular repair [average age, 35.4 years; 41% female patients] and 369 with nonrepair [average age, 37.3 years; 38% female patients]). In the included studies, surgical procedures consisting of labral repair and pincer or cam osteoplasty were performed via hip arthroscopy. The modified Harris Hip Score was measured in all the included studies, and the standardized mean difference in PROMs for capsular repair versus nonrepair in the included studies was 0.42 (95% confidence interval [CI], 0.20 to 0.63). A sensitivity analysis of randomized controlled trials achieved consistent results (standardized mean difference in PROMs, 0.31; 95% CI, 0.02 to 0.60). Capsular repair was not associated with a reduction in revision surgery (risk difference, -0.02; 95% CI, -0.06 to 0.03; 26 of 270 patients with capsular repair vs 42 of 369 with nonrepair) but was associated with a reduction in conversion to THA (risk difference, -0.05; 95% CI -0.09 to -0.01; 12 of 270 patients with capsular repair vs 38 of 369 with nonrepair). The average Methodological Index for Non-randomized Studies (MINORS) score in the included studies was 20. Conclusions: Patients who undergo capsular repair in conjunction with other arthroscopic hip preservation techniques have better PROMs and a lower incidence of THA conversion. Level of Evidence: Level II, systematic review of Level I and II investigations.

Biomechanical Analysis of Hip Braces after Hip Arthroscopic Surgery for Femoroacetabular Impingement Syndrome: An Observational Study.

Currently, hip braces are recommended and typically worn by femoroacetabular impingement (FAI) patients after hip arthroscopic surgery. However, there is currently a lack of literature regarding the biomechanical effectiveness of hip braces. The purpose of this study was to investigate the biomechanical effect of hip braces after hip arthroscopic surgery for FAI. Overall, 11 patients who underwent arthroscopic FAI correction and labral preservation surgery were included in the study. Standing-up and walking tasks in unbraced and braced conditions were performed at 3 weeks postoperatively. For the standing-up task, videotaped images of the hip's sagittal plane were recorded while patients stood from a seated position. After each motion, the hip flexion-extension angle was calculated. For the walking task, acceleration of the greater trochanter was measured using a triaxial accelerometer. For the standing-up motion, the mean peak hip flexion angle was found to be significantly lower in the braced condition than in the unbraced condition. Furthermore, the mean peak acceleration of the greater trochanter was significantly lower in the braced condition than in the unbraced condition. Patients undergoing arthroscopic FAI correction surgery would benefit from usage of a hip brace in terms of protecting repaired tissues during early postoperative recovery.

Delayed cortical bone healing due to impaired nuclear Nrf2 translocation in COPD mice.

The effect of the pathogenesis of chronic obstructive pulmonary disease (COPD) on bone fracture healing is unknown. Oxidative stress has been implicated in the systemic complications of COPD, and decreased activity of Nrf2 signaling, a central component of the in vivo antioxidant mechanism, has been reported. We investigated the process of cortical bone repair in a mouse model of elastase-induced emphysema by creating a drill hole and focusing on Nrf2 and found that the amount of new bone in the drill hole was reduced and bone formation capacity was decreased in the model mice. Furthermore, nuclear Nrf2 expression in osteoblasts was reduced in model mice. Sulforaphane, an Nrf2 activator, improved delayed cortical bone healing in model mice. This study indicates that bone healing is delayed in COPD mice and that impaired nuclear translocation of Nrf2 is involved in delayed cortical bone healing, suggesting that Nrf2 may be a novel target for bone fracture treatment in COPD patients.

Endoscopic Technique to Remove Endobutton After Anterior Cruciate Ligament Reconstruction.

Suture button-based femoral cortical suspension constructs of anterior cruciate ligament grafts may facilitate fast and secure fixation. The necessity of Endobutton removal is controversial. Many current surgical techniques do not allow direct visualization of the Endobutton(s), making it challenging to remove; the buttons are fully flipped without soft tissue interposition between the Endobutton and femur. This Technical Note demonstrates endoscopic removal of Endobuttons through the lateral femoral portal. This technique allows direct visualization facilitating easier hardware removal while harnessing the advantages of a less-invasive procedure.

Intra-articular injection versus interscalene brachial plexus block for acute-phase postoperative pain management after arthroscopic shoulder surgery.

BACKGROUND: The minimally invasive approach of arthroscopic shoulder surgery is beneficial; however, for optimal outcomes, perioperative pain management is essential. This cross-sectional study aimed to examine the analgesic effectiveness of intra-articular injection (IA) versus interscalene brachial plexus block (ISPB) among patients treated with arthroscopic shoulder surgeries. METHODS: We reviewed 100 consecutive patients who underwent shoulder arthroscopic surgery, of whom 50 each underwent IA (February 2019─January 2020; IA group) and ISPB (October 2018─July 2019; ISPB group). The primary outcome was the postoperative pain score measured using a Wong-Baker FACES Pain Rating Scale preoperatively and at 2, 6, 12, 24, and 48 h postoperatively. We performed multiple regression analysis to examine whether IA/ISPB selection is associated with acute-phase postoperative pain and adjusted for intra-articular injection, interscalene brachial plexus block, postoperative pain management, arthroscopic shoulder surgery, IA with 10 mg of morphine previously reported prognostic factors for postoperative pain (e.g., surgical procedures, operative time, older age, and preoperative pain). Furthermore, we examined induction time, total pentazocine dosage, and total postoperative nausea and vomiting (PONV) events. RESULTS: There were no significant differences between the IA and ISPB groups in perioperative pain control during the acute-phase periods (p = 0.12, repeated analysis of variance). The difference in anesthesia method was not a prognostic factor for acute-phase postoperative pain (p = 0.11). The IA group (15.06 ± 4.00 min) had a significantly shorter mean anesthesia induction time than the ISPB group (29.23 ± 9.22 min) (p = 0.0001). There was no significant between-group difference in the total pentazocine dosage during the first 7 days (p = 0.3934) postoperatively. PONV was observed in eight (17.0%) and two (4.2%) patients in the IA and ISPB groups, respectively. There was no significant between-group difference in the PONV incidence (p = 0.1582). CONCLUSIONS: There was no significant difference in acute-phase postoperative pain management between the IA and ISPB groups. The induction time was significantly shorter in IA. IRB: Approval number: UOEHCRB20-078, IRB approval date: September 9th, 2020; study duration: October 2018 to January 2020.

Association of combined hip-pelvic-lumbar mobility with hip muscle strength and clinical outcomes in patients treated for femoroacetabular impingement syndrome: A case-control study.

BACKGROUND: It is unclear whether hip and pelvic mobility in the sagittal plane are associated with hip function in FAIS. This study aimed to determine whether hip-pelvis-lumbar mobility is associated with preoperative hip function and postoperative outcomes in FAIS. METHODS: This was a level 3 case-control study. This study included 111 patients who underwent arthroscopic FAI correction and labral preservation between 2015 and 2019. The Hip-Pelvic-Lumbar Mobility Test (HPLMT) was performed preoperatively; hip flexion with the hip adducted and internally rotated was examined in the lateral decubitus position, and a total hip flexion angle of less than 120° was diagnosed as positive. HPLMT-positive patients were classified as cases, and HPLMT-negative patients were classified as controls. Hip muscle strength was measured preoperatively using a hand-held dynamometer. The modified Harris hip score (mHHS), Nonarthritic Hip Score (NAHS), and International Hip Outcome Tool-12 score were obtained preoperatively and postoperatively. The rates of patient acceptable symptomatic state (PASS) achievement for patient-reported outcome scores (PROSs) were compared between groups. RESULTS: The preoperative PROSs for the HPLMT-positive patients were significantly lower than those for the HPLMT-negative patients. HPLMT-positive patients had significantly weaker hip strength on the affected side than HPLMT-negative patients (flexion; p < 0.001, abduction; p = 0.001). HPLMT-positive patients had significantly lower postoperative mHHS than HPLMT-negative patients. HPLMT-positive patients were significantly less likely to achieve a PASS for the mHHS (62% versus 85%) and NAHS (48% versus 71%) than HPLMT-negative patients. CONCLUSION: Hip-pelvis-lumbar mobility is associated with hip function and clinical outcomes in FAIS patients. The HPLMT is an efficient tool for assessing FAIS patients.

Hip arthroscopic management for treating a rhythmic gymnast with a large bone cyst at the femoral head in the setting of hip dysplasia-a case report.

Recent literature lacks a clear understanding of how to manage bone cysts associated with hip dysplasia. This article aimed to report a case of hip dysplasia in a rhythmic gymnast surgically managed with arthroscopic retrograde bone grafting, labral repair, cam osteoplasty, double shoelace capsular closure and endoscopic shelf acetabuloplasty. A 20-year-old female college rhythmic gymnast presented complaining of right hip pain and discomfort for the past 2 months. This case report describes the use of the CROSSTRAC guide system to perform retrograde bone grafting to treat the bone cyst at the femoral head arthroscopically. Hip arthroscopic retrograde bone grafting, labral repair, cam osteoplasty, double shoelace capsular closure and endoscopic shelf acetabuloplasty are less invasive and beneficial for the treatment of bone cysts of the femoral head associated with hip dysplasia in symptomatic rhythmic gymnasts.

Biomechanical Evaluation of 4 Suture Techniques for Hip Capsular Closure.

Background: The most reliable suture technique for capsular closure after a capsulotomy remains unknown. Purpose: To determine which suture technique best restores native stability after a 5-cm interportal capsulotomy. Study Design: Controlled laboratory study. Methods: Ten human cadaveric hip specimens were tested using a 6-degrees-of-freedom robotic arm in 7 states: intact, capsular laxity, 5-cm capsulotomy, standard suture, shoelace, double shoelace, and Quebec City slider (QCS). Rotational range of motion (ROM) was measured across 9 tests: flexion, extension, abduction, abduction at 45° of flexion, adduction, external rotation, internal rotation, anterior impingement, and log roll. Distraction (ie, femoral head translation [FHT]) was measured across a range of flexion and abduction angles. Results: When compared with the native state, the 5-cm capsulotomy state showed the largest laxity increases on all tests, specifically in external rotation ROM (+13.4°), extension ROM (+11.5°), and distraction FHT (+4.5 mm) (P < .001 for all). The standard suture technique was not significantly different from the 5-cm capsulotomy on any test and demonstrated significantly more flexion ROM than the double shoelace suture (+1.41°; P = .049) and more extension ROM (+5.51°; P = .014) and external rotation ROM (+6.03°; P = .021) than the QCS. The standard suture also resulted in significantly higher distraction FHT as compared with the shoelace suture (+1.0 mm; P = .005), double shoelace suture (+1.4 mm; P < .001), and QCS (+1.1 mm; P = .003). The shoelace, double shoelace, and QCS techniques significantly reduced hip laxity when compared with the 5-cm capsulotomy state, specifically in external rotation ROM (respectively, -8.1°, -7.8°, and -10.2°), extension ROM (-6.3°, -7.3°, and -8.1°), and distraction FHT (-1.8, -2.2, and -1.9 mm) (P ≤ .003 for all). These 3 techniques restored native stability (no significant difference from intact) on some but not all tests, and no significant differences were observed among them on any test. Conclusion: Hip capsule closure with the standard suture technique did not prevent postoperative hip instability after a 5-cm capsulotomy, and 3 suture techniques were found to be preferable; however, none perfectly restored native stability at time zero. Clinical Relevance: The shoelace, double shoelace, and QCS suture techniques are recommended when closing the hip capsule.

Isolation and Characterization of Synovial Mesenchymal Stem Cells Derived From Patients With Chronic Lateral Ankle Instability: A Comparative Analysis of Synovial Fluid, Adipose Synovium, and Fibrous Synovium of the Ankle Joint.

Background: Synovial mesenchymal stem cells (MSCs) have high proliferative potential and are considered an excellent source for stem cell therapy. Purposes: To isolate MSCs from the synovium of ankle joints in patients with chronic lateral ankle instability (CLAI) and to compare the characteristics of MSCs derived from the synovium anterior to the talus with those from the surrounding anterior talofibular ligament (ATFL) synovium. Study Design: Controlled laboratory study. Methods: The synovium was harvested from 2 locations in the ankle, the synovium anterior to the talus and the surrounding ATFL synovium, of 14 patients who underwent arthroscopic ATFL repair for CLAI without osteochondral lesions of the talus (OLTs). Synovial fluid was also harvested. MSCs were isolated from both types of synovial tissue, as well as synovial fluid. The number of MSCs in the synovium and their viability, proliferation, colony-forming units, and potential to differentiate into adipose, bone, and cartilage tissues were determined and compared between groups. Additionally, real-time polymerase chain reaction was used to assess the differentiation capacity of adipose, bone, and cartilage tissues from both samples. The Wilcoxon signed rank test was used to compare the sample weight, number of colonies, number of nucleated cells per colony, yield obtained, and phenotypic characteristics of MSCs derived from different locations of the synovium. Results: No significant differences were observed in the sample weight (P = .051), number of nucleated cells per milligram (P = .272), number of colonies (P = .722), and yield obtained (P = .099) between the 2 groups. MSCs could not be isolated from synovial fluid. The frequency of oil red O-positive adipogenic colonies (P = .028) and the expression of the adipsin gene (P < .05) were significantly increased in the cells from the synovium anterior to the talus compared to those in the cells from the surrounding ATFL synovium. However, chondrogenic and osteogenic potentials were not significantly different between the 2 groups. Conclusion: Synovial MSCs obtained from the ankle joint had self-renewal and multilineage differentiation potential, although the adipogenesis potential of MSCs from the synovium anterior to the talus was superior to that from the surrounding ATFL synovium. Clinical Relevance: Both the adipose synovium and fibrous synovium in the ankle joints of patients with CLAI may be a good source of MSCs for stem cell therapy applications, whereas synovial fluid appeared unsuitable.

Accurate cup placement using a portable navigation system during total hip arthroplasty based on pelvic orientation in the lateral decubitus position.

BACKGROUND: We previously proposed an accurate cup placement procedure using a portable navigation system (PNS) for total hip arthroplasty (THA) in the lateral decubitus position; however, the accuracy of our proposed procedure has not been shown, the aim of this study was to demonstrate the accuracy. METHODS: We prospectively analyzed 79 hips treated with primary THA; 40 hips treated until June 2020 were included in the conventional procedure (CP) group, and 39 hips treated from July 2020 were included in the modified procedure (MP) group. In the MP, pelvic orientation is considered to be the set coordinate axes in addition to the CP using the PNS. The accuracy was based on the difference between the navigation record (NR) and postoperative computed tomography measurement. RESULTS: The radiographic inclination (RI) and anteversion (RA) accuracies were 1.55° and 2.14°, respectively, in the MP group and 3.03° and 6.20°, respectively, in the CP group (p < 0.001). The error was within 5° of the NR for both the RI and RA in 34 in the MP group (87.2%) and 14 in the CP group (35.0%) (p < 0.001). The error was within 5° of the target angle (RI 40°, RA 15°) for both the RI and RA in 29 hips in the MP group (74.7%) and 12 in the CP group (30.0%) (p < 0.001). CONCLUSIONS: Our procedure with the consideration of pelvic orientation achieved dramatically improved the accuracy of PNS and was suitable to facilitate accurate cup placement.

Cleft Sign and Bone Marrow Edema of the Pubic Symphysis Are Associated With Sports and Bony Morphology in Patients With Femoroacetabular Impingement and Labral Tears.

BACKGROUND: The cleft sign (CS) and bone marrow edema (BME) are considered magnetic resonance imaging (MRI) findings signifying a pubic pathology, which is associated with groin pain; however, their relationship with bony morphology related to femoroacetabular impingement (FAI) has not been established. PURPOSE: To investigate the prevalence of CS and BME in symptomatic patients with acetabular labral tears and assess their possible association with bone morphology and sport-specific activities. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: This study enrolled 418 patients (469 hips) undergoing hip arthroscopic surgery for labral tears. Also included were patients with labral tears in the setting of either hip dysplasia or borderline hip dysplasia who were undergoing endoscopic shelf acetabuloplasty combined with hip arthroscopic labral repair, cam osteoplasty, and capsular plication. All patients were screened for superior CS (SCS), inferior CS (ICS), and BME of the ipsilateral side of the pubis using 3-T MRI. We measured the following angles: lateral center edge (LCE), Sharp, Tönnis, vertical-central-anterior, and alpha. Then, we evaluated the relationship between patient characteristics and abnormal findings on MRI scans (preoperatively vs 1 year postoperatively). RESULTS: An overall 397 hips were included: 200 in men and 197 in women (mean ± SD age, 35.3 ± 16.0 years). There were hips in 214 athletes (53.9%) and hips in 183 nonathletes (46.1%). MRI findings revealed SCS, ICS, and BME in 18 (4.5%), 13 (3.3%), and 34 hips (8.6%), respectively. Abnormal MRI findings at the pubis were seen more often in athletes than nonathletes (23.8% vs 3.3%), and contact sports athletes had the most frequent abnormalities. There was no SCS in patients with an LCE angle <22°. SCS was more frequently seen in those who had an alpha angle ≥71°. More than 60% of abnormal findings at the pubis diminished after arthroscopic surgery that included FAI correction and labral repair. CONCLUSION: In patients with labral tears, CS and BME were seen more frequently in athletes versus nonathletes, especially contact athletes with FAI-related bony abnormalities. More than 60% of abnormal MRI pubis findings resolved after arthroscopic treatment of FAI.

Development of a novel knee contracture mouse model by immobilization using external fixation.

AIMS: Several studies have used animal models to examine knee joint contracture; however, few reports detail the construction process of a knee joint contracture model in a mouse. The use of mouse models is beneficial, as genetically modified mice can be used to investigate the pathogenesis of joint contracture. Compared to others, mouse models are associated with a lower cost to evaluate therapeutic effects. Here, we describe a novel knee contracture mouse model by immobilization using external fixation. METHODS: The knee joints of mice were immobilized by external fixation using a splint and tape. The passive extension range of motion (ROM), histological and immunohistochemical changes, and expression levels of fibrosis-related genes at 2 and 4 weeks were compared between the immobilized (Im group) and non-immobilized (Non-Im group) groups. RESULTS: The extension ROM at 4 weeks was significantly lower in the Im group than in the Non-Im group (p < 0.01). At 2 and 4 weeks, the thickness and area of the joint capsule were significantly greater in the Im group than in the Non-Im group (p < 0.01 in all cases). At 2 weeks, the mRNA expression levels of the fibrosis-related genes, except for the transforming growth factor-ß1, and the protein levels of cellular communication network factor 2 and vimentin in the joint capsule were significantly higher in the Im group (p < 0.01 in all cases). CONCLUSION: This mouse model may serve as a useful tool to investigate the etiology of joint contracture and establish new treatment methods.

Cotyloid Fossa Coverage Percentages May Be Associated With Alpha Angle, Labral Tear, and Clinical Outcomes in Patients With Femoroacetabular Impingement.

BACKGROUND: Within the hip joint, the anatomy of the acetabulum and cotyloid fossa is well established. There is little literature describing the association between the size of the cotyloid fossa relative to the acetabulum and characteristics of patients with femoroacetabular impingement (FAI). PURPOSE/HYPOTHESIS: The purpose was to calculate the cotyloid fossa coverage percentage in the acetabulum and determine its association with patient characteristics, radiographic parameters, intra-articular findings, and preoperative patient-reported outcomes in patients with FAI. We hypothesized there is an association between the cotyloid fossa coverage percentage of the acetabulum and characteristics of patients with FAI. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: Patients were included who underwent standard clinical 3-T magnetic resonance imaging of the hip and primary arthroscopic FAI correction surgery during 2015 and 2016. Exclusion criteria were age <18 or >40 years, osteoarthritis, labral reconstruction, previous ipsilateral hip surgery, and hip dysplasia. Measurements of the cotyloid fossa and surrounding lunate cartilage were performed to calculate cotyloid fossa width (CFW) and cotyloid fossa height (CFH) coverage percentages. The relationships between coverage percentages and patient characteristics and intraoperative findings were assessed using independent t tests or Pearson correlations. RESULTS: An overall 146 patients were included. Alpha angle negatively correlated with CFH coverage percentage (r = -0.19; P = .03) and positively correlated with labral tear size (r = 0.28; P < .01). CFH coverage percentage was negatively correlated with labral tear size (r = -0.24; P < .01). Among patients with degenerative tears, CFH was negatively correlated with labral tear size (r = -0.31; P < .01). However, this association was no longer significant after adjusting for sex (partial r = -0.10; P = .39). Cotyloid fossa coverage was not associated with the condition of the cotyloid fossa synovium (synovitis vs no synovitis). CFW coverage percentage was negatively correlated with the 12-Item Short Form Health Survey (SF-12) physical component summary score (r = -0.23; P < .01). CONCLUSION: The CFW and CFH coverage percentages may be associated with alpha angle, labral tear size, and SF-12 physical component summary score in patients with FAI. We may be able to predict the labral condition based on preoperative measurements of CFH and CFW coverage percentages.

Endoscopic Shelf Acetabuloplasty Concomitant With Labral Repair, Cam Osteoplasty, and Capsular Plication to Treat Acetabular Dysplasia in Artistic Athletes: A Case Series.

BACKGROUND: Knowledge of clinical outcomes and return to artistic activities after endoscopic shelf acetabuloplasty (ESA) for acetabular dysplasia in artistic athletes is lacking. HYPOTHESIS: Hip arthroscopic surgery including ESA will enable artistic athletes to return to their activities with a high success rate, significantly improved acetabular coverage, and preserved joint cartilage. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: We reviewed 28 hips in 23 female artistic athletes (14 ballet, 9 rhythmic gymnastics, 4 dance, and 1 baton twirling) who underwent arthroscopic labral preservation, capsular plication, and ESA. Their mean age was 25.8 ± 10.2 years. Preoperatively, all patients had generalized joint laxity (Beighton score, 7.1 ± 1.8). We evaluated preoperative and postoperative radiographs and outcome scores including the modified Harris Hip Score (mHHS), Nonarthritic Hip Score (NAHS), International Hip Outcome Tool 12 (iHOT-12), Vail Hip Score (VHS), and Hip Outcome Score-Sports (HOS- Sports). Statistical analysis was performed using paired t tests and Bonferroni correction. RESULTS: The mean follow-up was 32.5 ± 12.5 months. The mean lateral center-edge angle significantly increased from preoperatively (15.7° ± 5.3°) to postoperatively (39.8° ± 8.2°; P < .001) and at the final follow-up (33.7° ± 8.6°; P < .001). The vertical-center-anterior angle significantly improved from preoperatively (16.2° ± 8.8°) to final follow-up (33.6° ± 8.0°; P < .001). All hips maintained a Tönnis grade of 0 or 1 at the final follow-up. Overall, 20 patients (87%) were able to return to their preinjury level. All outcome scores improved from preoperatively to postoperatively: mHHS, from 68.5 ± 18.1 to 88.3 ± 18.5; NAHS, from 50.8 ± 17.7 to 69.0 ± 11.4; iHOT-12, from 36.9 ± 19.3 to 75.2 ± 19.8; VHS, from 53.8 ± 13.7 to 79.4 ± 19.4; and HOS--Sports, from 59.9 ± 17.0 to 79.6 ± 21.3 (P < .001 for all). In total, 3 patients could not return to artistic activities as the result of postoperative deep gluteal syndrome. CONCLUSION: ESA concomitant with labral repair, cam osteoplasty, and capsular plication to treat dysplastic hips in patients with joint laxity enabled artistic athletes to return to their activities with a high success rate.

Effect of metformin treatment and its time of administration on joint capsular fibrosis induced by mouse knee immobilization.

Joint contracture leads to major patient discomfort. Metformin, one of the most extensively used oral drugs against type 2 diabetes has recently been found to suppress tissue fibrosis as well. However, its role in suppressing tissue fibrosis in joint contractures remains unknown. In this study, we examined the role of metformin treatment in suppressing joint capsular fibrosis and the most effective time of its administration. Joint capsular fibrosis was induced by immobilizing the knee joints of mice using splints and tapes. Metformin was administered intraperitoneally every alternate day after immobilization. Histological and immunohistochemical changes and expression of fibrosis-related genes were evaluated. Metformin treatment significantly suppressed fibrosis in joint capsules based on histological and immunohistochemical evaluation. Joint capsular tissue from metformin-treated mice also showed decreased expression of fibrosis-related genes. Early, but not late, metformin administration showed the same effect on fibrosis suppression in joint capsule as the whole treatment period. The expression of fibrosis-related genes was most suppressed in mice administered with metformin early. These studies demonstrated that metformin treatment can suppress joint capsular fibrosis and the most effective time to administer it is early after joint immobilization; a delay of more than 2 weeks of administration is less effective.

Longitudinal study of risk factors for decreased cross-sectional area of psoas major and paraspinal muscle in 1849 individuals.

This 10-year retrospective observational study investigated longitudinal losses in psoas major and paraspinal muscle area in 1849 healthy individuals (1690 male, 159 female) screened using computed tomography. Logistic regression analysis revealed significant decreases in psoas major and paraspinal muscle area at 10 years relative to the baseline area regardless of age or sex, starting at 30 years of age. Only aging [≥ 50 s (odds ratio [OR]: 1.72; 95% confidence interval [CI] 1.05-2.84; p = 0.03) and ≥ 60 s (OR: 2.67; 95% CI 1.55-4.60; p < 0.001)] was a risk factor for decreases in psoas major area. Age ≥ 60 years (OR: 2.05; 95% CI 1.24-3.39; p = 0.005), body mass index ≥ 25 kg/m2 (OR: 1.32; 95% CI 1.01-1.73; p = 0.04), and visceral fat ≥ 100 cm2 (OR: 1.61; 95% CI 1.20-2.15; p = 0.001) were risk factors for decreases in paraspinal muscle area. Physical activity ≥ 900 kcal/week (OR: 0.68; 95% CI 0.50-0.94; p = 0.02) attenuated paraspinal muscle area loss in male. Our study demonstrated that walking > 45 min daily (Calories = METs (walking: 3.0) × duration of time (h) × weight (60 kg) × 1.05) can reduce paraspinal muscle loss, which may in turn decrease the risk of falls, low-back pain, and sarcopenia.

Elbow Ulnar Collateral Ligament Shoelace Repair with Internal Bracing for Treating Throwing Athletes Who Have Ulnar Collateral Ligament Instability.

This Technical Note aimed to present a surgical technique of ulnar collateral ligament (UCL) shoelace repair using suture anchors and double suture tapes in combination with internal bracing to correct UCL instability along with epiphyseal avulsion of the medial epicondyle in throwing athletes Skeletally immature throwing athletes playing baseball and softball are at a risk of sustaining medial epicondyle epiphyseal separation that can result in UCL instability, predisposing to elbow UCL disruption later. There are several surgical techniques that can restore elbow UCL function and stability. In cases where large fragments of the medial epicondyle are present in skeletally immature athletes, the residual bony fragment and the shortened, chronically injured UCL make surgical treatment quite challenging. Recent studies have shown that UCL repair with internal bracing can effectively treat acute UCL injury. However, this procedure is not ideal for restoring large disruption of the UCL such as fragmentation. Here, we present a surgical technique of UCL shoelace repair using suture anchors with double suture tapes in combination with internal bracing for correcting UCL instability concurrent with epiphyseal fragmentation of medial epicondyle in throwing athletes.