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Background: Unrepairable massive rotator cuff tears (UMRCTs) are challenging to surgeons owing to the severely retracted rotator cuff musculotendinous tissues and extreme defects in the rotator cuff tendinous tissues. Purpose: To fabricate a tendon stem cell–derived exosomes loaded scaffold (TSC-Exos-S) and investigate its effects on cellular bioactivity in vitro and repair in a rabbit UMRCT model in vivo. Study Design: Controlled laboratory study. Methods: TSC-Exos-S was fabricated by loading TSC-Exos and type 1 collagen (COL-I) into a 3-dimensional bioprinted and polycaprolactone (PCL)–based scaffold. The proliferation, migration, and tenogenic differentiation activities of rabbit bone marrow stem cells (BMSCs) were evaluated in vitro by culturing them in saline, PCL-based scaffold (S), COL-I loaded scaffold (COL-I-S), and TSC-Exos-S. In vivo studies were conducted on a rabbit UMRCT model, where bridging was repaired with S, COL-I-S, TSC-Exos-S, and autologous fascia lata (FL). Histological and biomechanical analyses were performed at 8 and 16 weeks postoperatively. Results: TSC-Exos-S exhibited reliable mechanical strength and subcutaneous degradation, which did not occur before tissue regeneration. TSC-Exos-S significantly promoted the proliferation, migration, and tenogenic differentiation of rabbit BMSCs in vitro. In vivo studies showed that UMRCT repaired with TSC-Exos-S exhibited significant signs of tendinous tissue regeneration at the bridging site with regard to specific collagen staining. Moreover, no significant differences were observed in the histological and biomechanical properties compared with those repaired with autologous FL. Conclusion: TSC-Exos-S achieved tendinous tissue regeneration in UMRCT by providing mechanical support and promoting the trend toward tenogenic differentiation. Clinical Relevance: The present study proposes a potential strategy for repairing UMRCT with severely retracted musculotendinous tissues and large tendinous tissue defects. [ABSTRACT FROM AUTHOR]

Background: The purpose of this trial was to determine whether anterior cruciate ligament reconstruction (ACLR) with anterolateral structure augmentation (ALSA) would result in better clinical outcomes in patients with a high risk of clinical failure.Methods: From February 2017 to June 2018, 120 young, active adults with chronic anterior cruciate ligament injury and high risk of clinical failure were randomized. The patients were followed for >2 years, with 5 being lost to follow-up and 1 being withdrawn from the study. Clinical characteristics, operative findings, and postoperative clinical outcomes were analyzed.Results: The analysis included data from 114 patients, including 95 men and 19 women with a mean age (and standard deviation) of 30.1 ± 6.7 years in the ACLR group and 30.1 ± 6.4 years in the ALSA group. The rate of clinical failure was 20.4% (11 of 54 patients) and 3.3% (2 of 60 patients) in the ACLR and ALSA groups, respectively (difference, 17.1%; 95% confidence interval [CI], 5.3% to 29.8%; p = 0.007). Significantly higher rates of return to the preinjury level of sports (48.3% versus 27.8%; difference, 20.5%; 95% CI, 2.7% to 36.6%; p = 0.024) and to a competitive level of play (63.3% versus 42.6%; difference, 22.3%; 95% CI, 4.1% to 38.8%; p = 0.027) was found in the ALSA group.Conclusions: Compared with isolated ACLR, combined ACLR and ALSA resulted in a reduction in persistent rotatory laxity and higher rates of return to preinjury and competitive levels of play at 2 years of follow-up in the population studied. Our study suggests that patients with high risk of clinical failure appear to be candidates for the ALSA approach.Level Of Evidence: Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence. [ABSTRACT FROM AUTHOR]

Background: Medial patellofemoral ligament (MPFL) reconstruction is one of the main treatments for lateral patellar translation. Based on intraoperative true lateral radiographs, the accepted methods for femoral MPFL tunnel location are potentially inaccurate. Direct assessment of anatomic characteristics during surgery through palpation of the anatomic landmarks involving the saddle sulcus might help eliminate tunnel malposition. Hypothesis: The saddle sulcus is a reliable osseous landmark where the MPFL attaches for tunnel placement. Study Design: Descriptive laboratory study. Methods: A total of 9 fresh-frozen unpaired human cadaveric knees were dissected; MPFL insertion point and relative osseous structures were marked. Three-dimensional images and transformed true lateral radiographs were obtained for analysis; 3 previously reported radiographic reference points for MPFL femoral tunnel placement were determined on all images and compared with the anatomic insertion. Results: A saddle sulcus consistently existed where the MPFL was attached, located at 11.7 ± 5.9 mm from the apex of the adductor tubercle (AT) to the medial epicondyle (ME), 62.8% of the average distance between the apexes of the AT and ME, and 5.6 ± 2.8 mm perpendicular-posterior to the border connecting the AT and ME. The reported radiographic reference points were located at average distances of 6.2 ± 3.2 mm (Schöttle method), 5.9 ± 2.3 mm (Redfern method), and 7.3 ± 6.6 mm (Fujino method) from the saddle sulcus center on the true lateral radiographs. Conclusion: The saddle sulcus was a reliable landmark where the MPFL was anatomically attached, located approximately 12 mm from the AT to the ME (approximately 60% along a line from the AT to the ME) and 6 mm perpendicular-posterior to the border connecting the apexes of the AT and ME. Additionally, the saddle sulcus position presented variability on the femoral aspect of different knees. All of the average direct distances from the sulcus to the reference radiographic points exceeded 5 mm, and tunnel localizations on a true lateral radiograph were inaccurate. Clinical Relevance: This study demonstrates the potential precise position of the saddle sulcus, according to the ME and AT, as a reliable anatomic landmark for MPFL femoral tunnel location. Radiographic reference points were not accurate during MPFL reconstruction. Direct palpation of the landmarks might be effective for femoral MPFL tunnel placement. [ABSTRACT FROM AUTHOR]

Objective: To observe the effect of preserving tibial residual fibers on the expressions of ligament remodeling related genes in rabbit anterior cruciate ligament (ACL) reconstruction model., Methods: Sixty healthy adult New Zealand white rabbits were randomly divided into 4 groups: normal control group (group A, n = 6), sham-operation group (group B, n = 18), non tibial remnant preserved group (group C, n = 18), and tibial remnant preserved group (group D, n = 18). At 2, 6, and 12 weeks after operation, the ligament tissue was harvested to detect the mRNA expressions of collagen type 1A1 (COL1A1), collagen type 3A1 (COL3A1), transforming growth factor β1 (TGF-β1), vascular endothelial growth factor (VEGF), growth-associated protein 43 (GAP-43), and neurotrophin 3 (NT-3) by real-time fluorescent quantitative PCR., Results: At each time point, there was no significant difference in the mRNA expressions of COL1A1, COL3A1, VEGF, and NT-3 between group A and group B (P > 0.05). In group D, the mRNA expressions of COL1A1, COL3A1, TGF-β1, and GAP-43 significantly increased when compared with those of group C at 6 weeks after operation (P < 0.05); an increased level of VEGF mRNA was also detected in the group D at 12 weeks after operation (P < 0.05); and an increased level of NT-3 mRNA was also observed in group D at 2 and 12 weeks after operation (P < 0.05)., Conclusion: There is a time-dependent manner of angiogenesis-promoting, repair-related, and nerve-related gene expressions after ACL reconstruction with preserving tibial residual fibers during the process of ligamentization. Furthermore, the remnant preservation in ACL reconstruction can promote the expressions of related genes in some time points.

Objective: To explore the technique of arthroscopic treatment of synovial chondromatosis of the hip and to evaluate its effectiveness., Methods: Between July 2009 and June 2011, 15 patients with synovial chondromatosis of the hip underwent arthroscopic synovectomy and removal of loose bodier. Of 15 patients, 11 were male and 4 were female, aged from 21 to 45 years with an average of 33.1 years. The location was the left side in 6 cases and the right side in 9 cases. The disease duration was 12-43 months (mean, 23 months) Pain and functional motion limitation were the main clinical symptoms. The visual analogue scale (VAS) score was 5.8 +/- 1.1; the range of motion (ROM) of the hip was (149.8 +/- 27.5)degrees; the Harris hip score was 54.5 +/- 13.3., Results: All incisions healed by first intention. All the patients were followed up 6 months to 2 years (mean, 17.4 months). At last follow-up, the VAS score was 2.0 +/- 1.2; the ROM of the hip was (258.3 +/- 35.4)degrees; the Harris hip score was 93.0 +/- 18.7; and the above indexes were significantly improved when compared with preoperative values (P < 0.05). No recurrence was found on postoperative MRI., Conclusion: Arthroscopic treatment of synovial chondromatosis of the hip has the advantages of minimal invasion, quick recovery, and best recovery of hip function and ROM.

Purpose: To explore whether changes in the starting point of separation affect the morphology of the 2 bundles of the anterior cruciate ligament (ACL) at insertion., Methods: Ten cadaveric knees were used to separate the ACL fibers into 2 bundles from 3 different starting points that were located at the proximal one fifth, two fifths, and three fifths of the inter-bundle mark line. The dividing lines between the 2 bundles at insertion and the area of the anteromedial (AM) bundle resulting from these different separations were compared, with data collected in groups I, II, and III, respectively., Results: The angle of the dividing line and the long axis of the femoral footprint was 67.24 degrees +/- 11.94 degrees, 91.01 degrees +/- 11.16 degrees, and 116.03 degrees +/- 9.01 degrees in groups I, II, and III, respectively, and the percentage of the AM bundle area in the whole femoral footprint was 38.64% +/- 5.55%, 52.22% +/- 6.76%, and 65.09% +/- 4.53%, respectively. At the tibial insertion sites, the angle between the dividing line and the sagittal plane was 110.17 degrees +/- 13.26 degrees, 127.72 degrees +/- 8.94 degrees, and 149.28 degrees +/- 18.80 degrees in groups I, II, and III, respectively, and the percentage of the AM bundle area in the whole footprint was 25.72% +/- 3.82%, 40.41% +/- 3.73%, and 60.56% +/- 6.59%, respectively. There were statistical differences between the angle and the area data of each of the 2 groups at either the tibial or femoral insertion site., Conclusions: In an anatomic study of the ACL, changes in the point from which separation started resulted in noticeably different bundle morphology at the insertion., Clinical Relevance: Proper separation will lead to a more accurate bundle description and, thus, a more accurate location of the tunnels in ACL reconstruction., ((c) 2010 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)