Effect of Porcine-Derived Absorbable Patch-Type Atelocollagen for Arthroscopic Rotator Cuff Repair: A Prospective Randomized Controlled Trial.

BACKGROUND: Even though arthroscopic rotator cuff repair is recognized as a standard treatment option, the risk of postoperative retear is a major concern. PURPOSE: To evaluate the effect of porcine-derived absorbable patch-type atelocollagen during arthroscopic rotator cuff repair. STUDY DESIGN: Randomized controlled trial; Level of evidence, 1. METHODS: A total of 64 patients with rotator cuff tears diagnosed on magnetic resonance imaging (MRI) were enrolled prospectively from November 2020 to December 2021. Both groups had repairs using the suture bridge technique. For the atelocollagen group, before securing the lateral anchors, we inserted porcine-derived absorbable patch-type atelocollagen between the footprint and the tendon. On postoperative day 2, the patients underwent MRI to confirm containment of the patch-type atelocollagen. At 6 months and 1 year postoperatively, the signal intensity of the repaired tendon was assessed using MRI. Patients were evaluated using the Constant score as the primary outcome, along with the visual analog scale for pain; range of motion; American Shoulder and Elbow Surgeons score; University of California, Los Angeles, score; and Korean Shoulder Score preoperatively and at 2, 3, 6, and 12 months postoperatively. RESULTS: No significant changes in the Constant score as primary outcome, pain or other functional scores, and range of motion were observed between the groups at 1 year postoperatively. The patch-type atelocollagen was confirmed to be contained by the time-zero MRI scan taken 2 days postoperatively. Among the 55 patients included in final analysis, 12 retear cases were recorded (21.8% retear rate). A significantly lower retear rate was found in the atelocollagen group, as 3 cases were observed in this group (10.3%) and 9 cases were observed in the conventional repair group (34.6%) (P = .048). CONCLUSION: The Constant score was not different between the groups. The retear rate after rotator cuff repair was significantly lower in the group that received porcine-derived absorbable patch-type atelocollagen compared with in the conventional group. REGISTRATION: KCT0005184 (Clinical Research Information Service [CRIS]; https://cris.nih.go.kr).

Plate prebending using a three-dimensional-printed model affords effective anatomical reduction in clavicular shaft fractures.

BACKGROUND: A precontoured plate rarely fits properly within the patient's clavicle and must be bent intraoperatively. This study aimed to determine whether anatomical reduction could be achieved using a plate bent before surgery. METHODS: This study included 87 consecutive patients with displaced mid-shaft clavicle fractures who underwent plate fixation and were followed-up for a minimum of 1 year. After exclusions, 39 consecutive patients underwent fixation with a precontoured plate bent intraoperatively (intraoperative bending group), and 28 underwent fixation with the plate bent preoperatively (preoperative bending group). Using free software and a three-dimensional (3D) printer, ipsilateral clavicle 3D-printed models were constructed. Using plain radiographs, the distance between the edge of the lateral inferior cortex and the medial inferior cortex was measured. The angle between the line connecting the inferior cortex edge and the line passing through the flat portion of the superior cortex of the distal clavicle was measured. RESULTS: Mean length differences between the ipsilateral and contralateral clavicle were smaller on both anteroposterior (AP; P=0.032) and axial images (P=0.029) in the preoperative bending group. The mean angular differences on both AP (P=0.045) and axial images (P=0.008) were smaller in the preoperative bending group. No significant differences were observed between the two groups in functional scores at the last follow-up. CONCLUSIONS: Smaller differences in length and angle between the ipsilateral and contralateral clavicle, indicative of reduction, were observed in the preoperative bending group. Using the precontoured technique with low expense, the operation was performed more effectively as reflected by a shorter operation time. Level of evidence: III.

Ultrasensitive Gas Detection Based on Electrically Enhanced Nanoplasmonic Sensor with Graphene-Encased Gold Nanorod.

Nanoplasmonic sensors are a widely known concept and have been studied with various applications. Among them, gas detection is engaging attention in many fields. However, the analysis performance of nanoplasmonic sensors based on refractive index confined to the metal nanostructure characteristics causes challenges in gas detection. In this study, we develop a graphene-encased gold nanorod (AuNR)-based nanoplasmonic sensor to detect cadaverine gas. The graphene-encased AuNR (Gr@AuNR) presents an ultrasensitive peak wavelength shift even with tiny molecules. In addition, the external potential transmitted through graphene induces an additional shift. A chemical receptor is immobilized on Gr@AuNR (CR@Gr@AuNR) for selectively capturing cadaverine. The CR@Gr@AuNR achieves ultrasensitive detection of cadaverine gas, and the detection limit is increased to 15.99 ppb by applying a voltage to graphene. Furthermore, the experimental results of measuring cadaverine generated from spoiled pork show the practicality of CR@Gr@AuNR. The strategy of external-boosted nanoplasmonics provides new insight into plasmonic sensing and applications.

Low Transcondylar Fractures of the Distal Humerus: A Multicenter Cohort Study.

OBJECTIVES: To determine the demographic characteristics and clinical and radiologic results of low transcondylar fractures and compare them with those of other types of distal humerus fractures using multicenter data and to suggest an optimal method for their treatment. DESIGN: Retrospective cohort study. SETTING: Tertiary-care university hospital. PATIENTS: Between 2009 and 2019, 581 patients who underwent surgery for distal humerus fractures (OTA/AO classification A1 to C3) were enrolled at 7 university-affiliated hospitals. INTERVENTION: Internal fixation of low transcondylar fractures. MAIN OUTCOME MEASURES: Demographic characteristics, including sex, age, mechanism of injury, fixation methods, and complications, were compared between low transcondylar (group A) and other distal humerus (group B) fractures. Clinical outcomes assessed included pain, stability, and range of motion. Radiographs obtained at the latest follow-up were assessed for union, delayed union, nonunion, and implant failure. RESULTS: Mean age was 62.1 ± 19.1 (range, 20-95) years, and it was higher in group A (n = 100) than in group B (n = 376). Patients in group A were predominantly women. Low-energy trauma, such as that from a simple fall, was the most common cause of fracture in group A. Both column fixation, including parallel and orthogonal double plating, was performed more commonly in group A than in group B (87.4% vs. 66.4%, P < 0.001). The nonunion rate was higher in group A, but the difference was not significant. The incidence of ulnar nerve-related symptoms was higher in group A after surgery (6.3% vs. 2.0%, P = 0.003). No significant difference in clinical outcomes was found between the groups. CONCLUSIONS: Low transcondylar fractures occurred more frequently than other distal humerus fractures in older female patients and accounted for 21% of distal humerus fractures. The incidence of ulnar nerve-related symptoms was higher in patients with low transcondylar fractures after surgery. Clinical outcomes were not inferior in patients with low transcondylar fractures. The nonunion rate in patients with low transcondylar fractures treated with double plating was 3.6%. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

A Propensity Score-Matched Comparison Between Knotless Layer-by-Layer and En Masse Suture Bridge Techniques for Delaminated Rotator Cuff Tears.

BACKGROUND: Because the articular layer is more prone to retraction than the bursal layer of the supraspinatus tendon, it is important to restore each layer anatomically while repairing delaminated rotator cuff tears (RCTs). PURPOSE: To compare clinical outcomes and tendon integrity between knotless layer-by-layer and conventional en masse repair techniques for delaminated RCTs. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: We retrospectively reviewed data from 174 consecutive patients with delaminated RCTs treated by arthroscopic suture bridge repair. Only 115 patients with medium to large supraspinatus tears with delamination were included. The 33 patients treated using the knotless layer-by-layer technique (group 2) were matched 1:1 with patients treated using en masse repair with the suture bridge technique (group 1) based on propensity scores. Tendon thickness was measured on magnetic resonance imaging (MRI). Signal changes in the bursal, articular, and intratendinous layers were assessed using T2-weighted MRI. RESULTS: Postoperatively, statistically significant improvements were seen in both groups compared with preoperatively functional scores. At the final follow-up, there was a statistically significant difference in the Constant score, which was higher in group 2 than in group 1 (91.4 ± 6.0 and 84.3 ± 16.4, respectively; P = .005). There was 1 case of a retear in each group, representing a 3% retear rate. Group 2 had thicker tendons than group 1 (6.9 ± 1.1 and 6.0 ± 1.2 mm, respectively; P = .017). On T2-weighted MRI, a low signal intensity in the articular layer was more common in group 2 (P = .046). CONCLUSION: En masse repair using the suture bridge technique and the knotless layer-by-layer technique were both effective. Regarding tendon healing, no significant differences were seen in retear rates. However, superior results in terms of the Constant score, tendon thickness, and signal intensity in the articular layer were observed using the knotless layer-by-layer technique.

Detection and discrimination of SARS-CoV-2 spike protein-derived peptides using THz metamaterials.

The development of effective assay techniques for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has recently received research attention due to its rapid worldwide spread and considerable risk to human health. The receptor-binding domain (RBD) of the spike (S) protein in SARS-CoV-2, a key component for viral entry that has a unique sequence compared to other structural proteins, has been considered an important diagnostic target. In this respect, low-frequency vibrational modes have the advantage of providing information about compositional and structural dependencies at the peptide level. In this study, the sensitive and selective detection of peptides derived from the RBD in SARS-CoV-2 and SARS-CoV was investigated using metamaterial-based sensing chips with a terahertz time-domain spectroscopy (THz-TDS) system. Based on their RBD sequences, two pairs of peptides with 20 residues each were prepared. The sensitivity, specificity, and reproducibility of the proposed system were examined via quantitative analysis using THz metamaterials at three resonance frequencies, and it was found that the species could be discriminated based on their sequences. The THz signals were analyzed with regard to the major amino acid components of the peptides, and the molecular distributions were also investigated based on the hydropathy and net charge of the peptides.

Why locking plates for the proximal humerus do not fit well.

INTRODUCTION: We compared the angle of the humerus and plate and to assess compatibility of a plate to the proximal humerus using three-dimensional (3D) printed models. MATERIALS AND METHODS: A total of 120 cases were included, who underwent anteroposterior shoulder radiographs. From these, 30 cases with 3D shoulder computed tomography scans were randomly selected to print 3D model. The lateral angle between the lateral cortex of the humeral shaft and lateral border of the greater tuberosity (GT), neck-shaft angle, and height from the most proximal point of the GT to the angular point were measured. When the plates were applied on the 3D models, the gap from the most proximal point of the GT to the proximal rim of the plate was measured. RESULTS: The mean lateral angle in plain radiographs was 12.9 ± 2.2° and height from the most proximal point of the GT to the angular point was 44.4 ± 4.7 mm. The bending angles of the three plates were 8° and 10°. Height from the proximal rim of the plate to the bending point was 42.4, 42.0 and 43.8 mm. In 98% of cases, the lateral angle of the humerus was larger than all three plates. In 43% of cases, height of the GT was smaller than height of plates. When plates were applied to the 3D model, the mean gap from GT to plate was 4.8 ± 2.8 mm. CONCLUSIONS: There was large variation in the lateral angle of the proximal humerus, which was not correlated with the neck-shaft angle. The lateral angle of the humerus was larger than the plates and prone to varus reduction and medial collapse. LEVEL OF EVIDENCE OR CLINICAL RELEVANCE: Basic science study.

Ultrasound Findings Aid Decisions to Repair Partial Articular Supraspinatus Tendon Avulsion.

OBJECTIVES: Ultrasound (US) is useful for diagnosing full-thickness rotator cuff tears and high-grade partial-thickness bursal-side tears. However, anisotropy artifacts make it difficult to identify partial articular supraspinatus tendon avulsion (PASTA) by US. This study was performed to determine the diagnostic accuracy of US for PASTA and to uncover sensitive findings that could aid decisions to repair. METHODS: Patients who underwent preoperative US examinations and supraspinatus tendon confirmation by arthroscopic examinations were enrolled. We analyzed 52 PASTA cases involving greater than 50% thickness of the tendon and 52 age- and sex-matched cases with an intact supraspinatus. Two orthopedic surgeons blinded to the diagnosis interpreted US videos of the supraspinatus tendon. Six findings (echo defect, tendon delamination, echo change, tendon thickness, tendon fiber pattern, and cartilage interface sign) were assessed. We calculated the sensitivity, specificity, and accuracy for each US finding. RESULTS: The cases consisted of 46 men and 58 women. The US diagnosis of PASTA showed sensitivity of 64.7%, specificity of 94.1%, and accuracy of 79.4%. The echo change in the short axis showed the highest sensitivity. Thinning and delamination showed the highest specificity of 100%. In contrast to previous reports, the sensitivity of the cartilage interface sign was low in both long-axis images (17.6%) and short-axis images (29.4%). CONCLUSIONS: Preoperative diagnostic US to aid decisions regarding PASTA repair showed high specificity (94.1%) and moderate accuracy (79.4%). However, the sensitivity was only 64.7% and was affected by the examiner's experience with US.

High-Performance Conducting Polymer Nanotube-based Liquid-Ion Gated Field-Effect Transistor Aptasensor for Dopamine Exocytosis.

In this study, ultrasensitive and precise detection of a representative brain hormone, dopamine (DA), was demonstrated using functional conducting polymer nanotubes modified with aptamers. A high-performance aptasensor was composed of interdigitated microelectrodes (IMEs), carboxylated polypyrrole nanotubes (CPNTs) and DA-specific aptamers. The biosensors were constructed by sequential conjugation of CPNTs and aptamer molecules on the IMEs, and the substrate was integrated into a liquid-ion gating system surrounded by pH 7.4 buffer as an electrolyte. To confirm DA exocytosis based on aptasensors, DA sensitivity and selectivity were monitored using liquid-ion gated field-effect transistors (FETs). The minimum detection level (MDL; 100 pM) of the aptasensors was determined, and their MDL was optimized by controlling the diameter of the CPNTs owing to their different capacities for aptamer introduction. The MDL of CPNT aptasensors is sufficient for discriminating between healthy and unhealthy individuals because the total DA concentration in the blood of normal person is generally determined to be ca. 0.5 to 6.2 ng/mL (3.9 to 40.5 nM) by high-performance liquid chromatography (HPLC) (this information was obtained from a guidebook "Evidence-Based Medicine 2018 SCL " which was published by Seoul Clinical Laboratory). The CPNTs with the smaller diameters (CPNT2: ca. 120 nm) showed 100 times higher sensitivity and selectivity than the wider CPNTs (CPNT1: ca. 200 nm). Moreover, the aptasensors based on CPNTs had excellent DA discrimination in the presence of various neurotransmitters. Based on the excellent sensing properties of these aptasensors, the DA levels of exogeneous DA samples that were prepared from PC12 cells by a DA release assay were successfully measured by DA kits, and the aptasensor sensing properties were compared to those of standard DA reagents. Finally, the real-time response values to the various exogeneous DA release levels were similar to those of a standard DA aptasensor. Therefore, CPNT-based aptasensors provide efficient and rapid DA screening for neuron-mediated genetic diseases such as Parkinson's disease.

Peptide hormone sensors using human hormone receptor-carrying nanovesicles and graphene FETs.

Hormones within very low levels regulate and control the activity of specific cells and organs of the human body. Hormone imbalance can cause many diseases. Therefore, hormone detection tools have been developed, particularly over the last decade. Peptide hormones have a short half-life, so it is important to detect them within a short time. In this study, we report two types of peptide hormone sensors using human hormone receptor-carrying nanovesicles and graphene field-effect transistors (FETs). Parathyroid hormone (PTH) and glucagon (GCG) are peptide hormones present in human blood that act as ligands to G protein-coupled receptors (GPCRs). In this paper, the parathyroid hormone receptor (PTHR) and the glucagon receptor (GCGR) were expressed in human embryonic kidney-293 (HEK-293) cells, and were constructed as nanovesicles carrying the respective receptors. They were then immobilized onto graphene-based FETs. The two hormone sensors developed were able to detect each target hormone with high sensitivity (ca. 100 fM of PTH and 1 pM of GCG). Also, the sensors accurately recognized target hormones among different types of peptide hormones. In the development of hormone detection tools, this approach, using human hormone receptor-carrying nanovesicles and graphene FETs, offers the possibility of detecting very low concentrations of hormones in real-time.

Ultrasensitive, Selective, and Highly Stable Bioelectronic Nose That Detects the Liquid and Gaseous Cadaverine.

Field-effect transistor (FET) devices based on conductive nanomaterials have been used to develop biosensors. However, development of FET-based biosensors that allow efficient stability, especially in the gas phase, for obtaining reliable and reproducible responses remains a challenge. In this study, we developed a nanodisc (ND)-functionalized bioelectronic nose (NBN) based on a nickel (Ni)-decorated carboxylated polypyrrole nanoparticle (cPPyNP)-FET that offers the detection of liquid and gaseous cadaverine (CV). The TAAR13c, specifically binding to CV, which is an indicator of food spoilage, was successfully constructed in NDs. The NBN was fabricated by the oriented assembly of TAAR13c-embedded NDs (T13NDs) onto the transistor with Ni/cPPyNPs. The NBN showed high performance in selectivity and sensitivity for the detection of CV, with excellent stability in both aqueous and gas phases. Moreover, the NBN allowed efficient measurement of corrupted real-food samples. It demonstrates the ND-based device can allow the practical biosensor that provides high stability in the gas phase.

Rotating Arm Internally Can Change the Arthroscopic Diagnosis of a Partial-thickness Tear of the Subscapularis.

BACKGROUND: The aims of this study were (1) to examine the footprint of the subscapularis tendon using the traditional posterior portal and 30° arthroscope by simple internal rotation of the arm during surgery, and (2) to classify the pattern of a subscapularis partial-thickness tear. METHODS: This study analyzed a total of 231 patients with a partial-thickness subscapularis tear from 550 consecutive patients undergoing an arthroscopic operation who had a visualization of the subscapularis tendon footprint by internal rotation of the arm. First, the patients were classified into four categories according to the tear pattern: (1) stable lamination, (2) unstable lamination, (3) avulsion, and (4) laminated avulsion. Randomized arthroscopic videos were reviewed blindly by two independent orthopedic surgeons. The pattern of the tear of the subscapularis at the neutral position and after internal rotating the arm were assessed and compared with the treatment decision (level IV case series). RESULTS: Stable lamination, unstable lamination, avulsion, and laminated avulsion were observed in 9.1% (n=21), 20.8% (n=48), 41.1% (n=95), and 29.0% (n=67) of cases, respectively. In 145 out of 231 cases (62.8%), the decision was changed after inspecting the footprint after internal rotation of the arm, and the treatment method was changed in 116 (50.2%) cases. CONCLUSIONS: In a subscapularis tendon partial-thickness tear, inspecting the footprint of the subscapularis tendon is essential to diagnosing and deciding on the appropriate treatment. In addition, simply internal rotating the arm during surgery when using the traditional posterior portal and 30° arthroscope can be a valuable method.

Analysis of Greater Tuberosity from the Center of the Humeral Head: Progression to Femoralization.

BACKGROUND: Progression of the tear size and erosion of the greater tuberosity (femoralization) in the supraspinatus tear makes it difficult to repair or increases the risk of a re-tear. This study examined the proximal articular surface and greater tuberosity of the humeral head in plain radiography. METHODS: Two-hundred forty-seven cases, whose anteroposterior (AP) radiographs were taken correctly, were included from 288 cases, in whom the status of the supraspinatus had been confirmed by surgery. After downloading the plain AP radiograph as DICOM, the radius of the circle apposed at the superior half of the articular surface of the head, and the distance between the circle and the farthest point of the greater tuberosity ('height' of the greater tuberosity) were calculated using the software (TechHime, Korea). MRI checked the number of torn tendons and degree of muscular atrophy. RESULTS: The following were encountered: 93 intact supraspinatus, 50 partial-thickness tears, and 104 full-thickness tears. In the analysis using the 93 intact cases, the average radius of the rotation center was 25.3 mm in male and 22.3 mm in female. The average height of the greater tuberosity from the circle with the same rotation center was 4.3 mm in male and 4.2 mm in female with no statistical significance. The correlation between the reparability of supraspinatus and height of the greater tuberosity, fatty infiltration, and muscular atrophy was confirmed. CONCLUSIONS: The height of the greater tuberosity from the circle with the same rotation center was 4.3 mm in male and 4.2 mm in female. This height was strongly correlated with muscular atrophy and fatty infiltration of the supraspinatus tendon.

Atelocollagen Enhances the Healing of Rotator Cuff Tendon in Rabbit Model.

BACKGROUND: Failure of rotator cuff healing is a common complication despite the rapid development of surgical repair techniques for the torn rotator cuff. PURPOSE: To verify the effect of atelocollagen on tendon-to-bone healing in the rabbit supraspinatus tendon compared with conventional cuff repair. STUDY DESIGN: Controlled laboratory study. METHODS: A tear of the supraspinatus tendon was created and repaired in 46 New Zealand White rabbits. They were then randomly allocated into 2 groups (23 rabbits per group; 15 for histological and 8 for biomechanical test). In the experimental group, patch-type atelocollagen was implanted between bone and tendon during repair; in the control group, the torn tendon was repaired without atelocollagen. Each opposite shoulder served as a sham (tendon was exposed only). Histological evaluation was performed at 4, 8, and 12 weeks. Biomechanical tensile strength was tested 12 weeks after surgery. RESULTS: Histological evaluation scores of the experimental group (4.0 ± 1.0) were significantly superior to those of the control group (7.7 ± 2.7) at 12 weeks ( P = .005). The load to failure was significantly higher in the experimental group (51.4 ± 3.9 N) than in the control group (36.4 ± 5.9 N) ( P = .001). CONCLUSION: Histological and biomechanical studies demonstrated better results in the experimental group using atelocollagen in a rabbit model of the supraspinatus tendon tear. CLINICAL RELEVANCE: Atelocollagen patch could be used in the cuff repair site to enhance healing.

Dual-Color Emissive Upconversion Nanocapsules for Differential Cancer Bioimaging In Vivo.

Early diagnosis of tumor malignancy is crucial for timely cancer treatment aimed at imparting desired clinical outcomes. The traditional fluorescence-based imaging is unfortunately faced with challenges such as low tissue penetration and background autofluorescence. Upconversion (UC)-based bioimaging can overcome these limitations as their excitation occurs at lower frequencies and the emission at higher frequencies. In this study, multifunctional silica-based nanocapsules were synthesized to encapsulate two distinct triplet-triplet annihilation UC chromophore pairs. Each nanocapsule emits different colors, blue or green, following a red light excitation. These nanocapsules were further conjugated with either antibodies or peptides to selectively target breast or colon cancer cells, respectively. Both in vitro and in vivo experimental results herein demonstrate cancer-specific and differential-color imaging from single wavelength excitation as well as far greater accumulation at targeted tumor sites than that due to the enhanced permeability and retention effect. This approach can be used to host a variety of chromophore pairs for various tumor-specific, color-coding scenarios and can be employed for diagnosis of a wide range of cancer types within the heterogeneous tumor microenvironment.

Self-assembled RNA-triple-helix hydrogel scaffold for microRNA modulation in the tumour microenvironment.

The therapeutic potential of miRNA (miR) in cancer is limited by the lack of efficient delivery vehicles. Here, we show that a self-assembled dual-colour RNA-triple-helix structure comprising two miRNAs-a miR mimic (tumour suppressor miRNA) and an antagomiR (oncomiR inhibitor)-provides outstanding capability to synergistically abrogate tumours. Conjugation of RNA triple helices to dendrimers allows the formation of stable triplex nanoparticles, which form an RNA-triple-helix adhesive scaffold upon interaction with dextran aldehyde, the latter able to chemically interact and adhere to natural tissue amines in the tumour. We also show that the self-assembled RNA-triple-helix conjugates remain functional in vitro and in vivo, and that they lead to nearly 90% levels of tumour shrinkage two weeks post-gel implantation in a triple-negative breast cancer mouse model. Our findings suggest that the RNA-triple-helix hydrogels can be used as an efficient anticancer platform to locally modulate the expression of endogenous miRs in cancer.

Locked bucket-handle type bony Bankart lesion resulting from manipulation.

A patient who underwent manipulation for stiffness accompanying a rotator cuff tear experienced a complication consisting of a bony Bankart lesion connected to the superior and inferior labrum. This lesion was displaced posteriorly, locked behind the humeral head and blocking the reduction. Attachment of the labrum to this fragment made reduction and fixation easier. This bony Bankart lesion was fixed successfully by arthroscopic placement of knotless suture anchors. Level of evidence Case report, Level IV.

Clinical outcome of arthroscopic SLAP repair: conventional vertical knot versus knotless horizontal mattress sutures.

PURPOSE: Arthroscopic repair of type II superior labrum anterior to posterior (SLAP) tears yields variable results. In this study, the clinical outcomes of arthroscopic knotless horizontal mattress repair were compared to those of conventional vertical knot repair. METHODS: Forty-six patients treated arthroscopically for isolated SLAP lesions were assessed. Forty-one of those patients underwent follow-up evaluations for a minimum of 2 years: 21 received vertical knot (group 1), while 20 received horizontal mattress (group 2). In group 1, an anchor was inserted at the superior glenoid. After relaying the sutures, knotting over the labral tissue was performed. In group 2, two strands were passed through the labrum and fixed into the glenoid with a bioabsorbable knotless anchor. Functional scores were evaluated preoperatively and at the final follow-up assessment. A visual analogue scale (VAS) for pain and range of motion (ROM) were assessed preoperatively, 2 months postoperatively and at the last follow-up visit. RESULTS: There were no significant differences in functional scores between groups (n.s.). However, external rotation at the side, internal rotation at abduction and total ROM were better in group 2 at the last follow-up visit. At 2 months postoperatively, the VAS for pain and ROM of internal rotation at abduction were better in group 2. CONCLUSION: At the final assessment, there were no significant differences in functional scores between the two groups. However, external rotation at the side, internal rotation at abduction and total ROM were better in group 2. LEVEL OF EVIDENCE: Case-control study, Level III.

Outcome Comparison Between in Situ Repair Versus Tear Completion Repair for Partial Thickness Rotator Cuff Tears.

PURPOSE: To compare the clinical outcomes of arthroscopic in situ repair with the tear completion repair technique for partial-thickness rotator cuff tears (PT-RCTs). METHODS: We prospectively enrolled 100 cases with articular-sided and bursal-sided PT-RCTs exceeding 50% of tendon thickness and allocated them randomly. An in situ repair was performed in group 1 (n = 50). Completion of the remaining cuff tissue and repair were performed in group 2 (n = 50). The medial row was knotted as transosseous repair (suture-bridge technique) in all cases. American Shoulder Elbow Society (ASES) score, Constant shoulder (CS) score, Simple shoulder (SS) score, and Korean shoulder (KS) score, and visual analog scale (VAS) for pain and range of motion were assessed at 3, 6, and 12 months and at the last visit. Repaired tendon integrity was determined at 6 to 12 months by magnetic resonance imaging. RESULTS: Eight cases were lost to follow-up. Ultimately, 92 cases were analyzed. The average follow-up was 19.1 months (range, 12 to 42 months). Significant improvements in the VAS for pain and functional outcomes were observed in both groups postoperatively (P = .001 for VAS; P < .001 for ASES score; P < .001 for CS score; P = .001 for SS score; P<.001 for KS score). No significant difference in the clinical results was observed at any time between the groups. No difference of retear rate on articular-sided PT-RCT was observed between the groups (P = .34). Retears on the bursal-sided PT-RCT were more frequent in group 2 (P = .02). CONCLUSIONS: Arthroscopic repair of PT-RCT exceeding 50% of the thickness provided functional improvements and pain relief regardless of the repair technique. The retear rate for bursal-sided PT-RCT was higher in group 2, although the retear rate for the articular-sided PT-RCT was not different. LEVEL OF EVIDENCE: Level II, prospective comparative study.

Personalizing Biomaterials for Precision Nanomedicine Considering the Local Tissue Microenvironment.

New advances in (nano)biomaterial design coupled with the detailed study of tissue-biomaterial interactions can open a new chapter in personalized medicine, where biomaterials are chosen and designed to match specific tissue types and disease states. The notion of a "one size fits all" biomaterial no longer exists, as growing evidence points to the value of customizing material design to enhance (pre)clinical performance. The complex microenvironment in vivo at different tissue sites exhibits diverse cell types, tissue chemistry, tissue morphology, and mechanical stresses that are further altered by local pathology. This complex and dynamic environment may alter the implanted material's properties and in turn affect its in vivo performance. It is crucial, therefore, to carefully study tissue context and optimize biomaterials considering the implantation conditions. This practice would enable attaining predictable material performance and enhance clinical outcomes.