The effect of erythropoietin on rat rotator cuff repair model: An experimental study

Objectives:The aim of this study was to determine whether erythropoietin (EPO) can enhance rotator cuff healing in rats as measured by histological analysis and biomechanical testing.Methods:A total of 72 rats were included in this study. In the control group ( n = 24), repair was performed without EPO injection. In the local group ( n = 24) EPO was injected in the repair site. In the systemic group ( n = 24) EPO was administered as an intraperitoneal injection every day for 10 days after repair. Rats were euthanized on day 10 ( n = 12 from each group) and day 28 ( n = 12 from each group). Histopathological ( n = 6) and biomechanical examinations ( n = 6) were done.Results:Biomechanical results reveal that the maximum load to failure values of the early control group were statistically lower than those of the early systemic group ( p = 0.006). Comparing the the total Bonar values histopathologically reveal that the early systemic group was statistically higher than those of the early local group ( p = 0.043). The late control group was statistically higher than those of the late local group ( p = 0.003) and the late systemic group ( p = 0.034). The late systemic group was statistically higher than those of the late local group ( p = 0.003).Conclusions:EPO application had a positive effect biomechanically in the early euthanized group and histopathologically in the late euthanized group.

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Atelocollagen Enhances the Healing of Rotator Cuff Tendon in Rabbit Model

The American Journal of Sports Medicine ◽

10.1177/0363546517703336 ◽

2017 ◽

Vol 45 (9) ◽

pp. 2019-2027 ◽

Cited By ~ 21

Author(s):

Dong-Sam Suh ◽

Jun-Keun Lee ◽

Ji-Chul Yoo ◽

Sang-Hun Woo ◽

Ga-Ram Kim ◽

...

Keyword(s):

Rotator Cuff ◽

Rapid Development ◽

Rabbit Model ◽

Supraspinatus Tendon ◽

Histological Evaluation ◽

Control Group ◽

Patch Type ◽

Load To Failure ◽

Cuff Repair ◽

Experimental Group

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.

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Small Subchondral Drill Holes Improve Marrow Stimulation of Rotator Cuff Repair in a Rabbit Model of Chronic Rotator Cuff Tear

The American Journal of Sports Medicine ◽

10.1177/0363546519896350 ◽

2020 ◽

Vol 48 (3) ◽

pp. 706-714 ◽

Cited By ~ 1

Author(s):

Yucheng Sun ◽

Jae-Man Kwak ◽

Erica Kholinne ◽

Youlang Zhou ◽

Jun Tan ◽

...

Keyword(s):

Rotator Cuff ◽

Rotator Cuff Repair ◽

Large Diameter ◽

Biomechanical Testing ◽

Rabbit Model ◽

Small Diameter ◽

Histological Evaluation ◽

Control Group ◽

Greater Tuberosity ◽

Cuff Repair

Background: Microfracture of the greater tuberosity has been proved effective for enhancing tendon-to-bone healing after rotator cuff repair. However, no standard diameter for the microfracture has been established. Purpose/Hypothesis: This study aimed to assess treatment with large- and small-diameter microfractures to enhance healing during rotator cuff repair surgery in a rabbit model of chronic rotator cuff tear. It was hypothesized that a small-diameter microfracture had advantages in terms of tendon-to-bone integration, bone-tendon interface maturity, microfracture healing, and biomechanical properties compared with a large-diameter microfracture. Study Design: Controlled laboratory study. Methods: Bilateral supraspinatus tenotomy from the greater tuberosity was performed on 21 New Zealand White rabbits. Bilateral supraspinatus repair was performed 6 weeks later. Small-diameter (0.5 mm) microfracture and large-diameter microfracture (1 mm) were performed on the left side and right side, respectively, in 14 rabbits as a study group, and simple repair without microfracture was performed in 7 rabbits as a control group. At 12 weeks later, 7 of 14 rabbits in the study group were sacrificed for micro–computed tomography evaluation and biomechanical testing. Another 6 rabbits were sacrificed for histological evaluation. In the control group, 3 of the 7 rabbits were sacrificed for histological evaluation and the remaining rabbits were sacrificed for biomechanical testing. Results: Significantly better bone-to-tendon integration was observed in the small-diameter microfracture group. Better histological formation and maturity of the bone-tendon interface corresponding to better biomechanical results (maximum load to failure and stiffness) were obtained on the small-diameter microfracture side compared with the large-diameter side and the control group. The large-diameter microfracture showed worse radiographic and histological properties for healing of the microfracture holes on the greater tuberosity. Additionally, the large-diameter microfracture showed inferior biomechanical properties but similar histological results compared with the control group. Conclusion: Small-diameter microfracture showed advantages with enhanced rotator cuff healing for biomechanical, histological, and radiographic outcomes compared with large-diameter microfracture, and large-diameter microfracture may worsen the rotator cuff healing. Clinical Relevance: This animal study suggested that a smaller diameter microfracture may be a better choice to enhance healing in clinical rotator cuff repair surgery in humans.

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Effect of Microcurrent Stimulation on Pain, Shoulder Function, and Grip Strength in Early Post-Operative Phase after Rotator Cuff Repair

Medicina ◽

10.3390/medicina57050491 ◽

2021 ◽

Vol 57 (5) ◽

pp. 491

Author(s):

Donghyun Yi ◽

Hwanyong Lim ◽

Jongeun Yim

Keyword(s):

Rotator Cuff ◽

Grip Strength ◽

Rotator Cuff Repair ◽

Controlled Trial ◽

Shoulder Function ◽

Control Group ◽

Simple Shoulder Test ◽

General Physical ◽

Cuff Repair ◽

Experimental Group

Background and Objectives: The purpose of this study was to investigate the effects of microcurrent stimulation on pain, shoulder function, and grip strength in patients with rotator cuff repair. Materials and Methods: This randomized single-blind controlled trial was conducted on inpatients of the rehabilitation department, and included 28 patients who underwent rotator cuff repair. Participants were randomly assigned to the experimental group (n = 14), treated with microcurrent stimulation, and the control group (n = 14), treated with false microcurrent stimulation. The microcurrent stimulation administered to the experimental group underwent general physical therapy and microcurrent stimulation three times a week for 4 weeks. Results: Changes in pain, range of motion in shoulder, simple shoulder test, and grip strength were assessed before and after the intervention. Both groups showed a significant decrease in pain and shoulder function (t = 27.412, 22.079, 19.079, and 18.561; p < 0.001), and grip strength showed a significant increase (t = −8.251 and −9.946; p < 0.001). The experimental group that underwent microcurrent stimulation exhibited a significant effect on pain, shoulder function, and grip strength compared with the control group that underwent false microcurrent stimulation (t = −2.17, −2.22, and 2.213; p = 0.039, 0.035, and 0.036). Conclusions: This study confirmed that microcurrent stimulation is effective for the treatment of rotator cuff repair patients.

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Greater Tuberosity Decortication Decreases Load to Failure of All-Suture Anchor Constructs in Rotator Cuff Repair

Arthroscopy The Journal of Arthroscopic and Related Surgery ◽

10.1016/j.arthro.2018.05.030 ◽

2018 ◽

Vol 34 (10) ◽

pp. 2777-2781 ◽

Cited By ~ 7

Author(s):

John A. Ruder ◽

Ephraim Y. Dickinson ◽

Richard D. Peindl ◽

Nahir A. Habet ◽

James E. Fleischli

Keyword(s):

Rotator Cuff ◽

Rotator Cuff Repair ◽

Suture Anchor ◽

Greater Tuberosity ◽

Load To Failure ◽

Cuff Repair

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The Role of Indian Hedgehog Signaling in Tendon Response to Subacromial Impingement: Evaluation Using a Mouse Model

The American Journal of Sports Medicine ◽

10.1177/03635465211062244 ◽

2021 ◽

pp. 036354652110622

Author(s):

Yulei Liu ◽

Xiang-Hua Deng ◽

Xueying Zhang ◽

Ting Cong ◽

Daoyun Chen ◽

...

Keyword(s):

Rotator Cuff ◽

Hedgehog Signaling ◽

Molecular Mechanisms ◽

Healing Process ◽

Biomechanical Testing ◽

Indian Hedgehog ◽

Control Group ◽

Subacromial Impingement ◽

Subacromial Space ◽

Gradual Improvement

Background: The underlying cellular and molecular mechanisms involved in the development of tendinopathy due to subacromial supraspinatus tendon (SST) impingement and the response to subsequent removal of impingement remain unknown. Purpose: To investigate the involvement of Indian hedgehog (IHH) signaling in the development of SST tendinopathy and the subsequent healing process after the relief of subacromial impingement in a novel mouse shoulder impingement model. Study Design: Controlled laboratory study. Methods: A total of 48 male wild-type C57BL/6 mice were used in this study. Supraspinatus tendinopathy was induced by inserting a microsurgical clip into the subacromial space bilaterally. Eleven mice were sacrificed at 4 weeks after surgery to establish impingement baseline; 24 mice underwent clip removal at 4 weeks after surgery and then were euthanized at 2 or 4 weeks after clip removal. Thirteen mice without surgical intervention were utilized as the control group. All SSTs were evaluated with biomechanical testing; quantitative histomorphometry after staining with hematoxylin and eosin, Alcian blue, and picrosirius red; and immunohistochemical staining (factor VIII, IHH, Patched1 [PTCH1], and glioma-associated oncogene homolog 1 [GLI1]). Results: The mean failure force and stiffness in the 4-week impingement group decreased significantly compared with the control group ( P < .001) and gradually increased at 2 and 4 weeks after clip removal. Histological analysis demonstrated increased cellularity and disorganized collagen fibers in the SST, with higher modified Bonar scores at 4 weeks, followed by gradual improvement after clip removal. The IHH-positive area and PTCH1- and GLI1-positive cell percentages significantly increased after 4 weeks of clip impingement (20.64% vs 2.06%, P < .001; 53.9% vs 28.03%, P = .016; and 30% vs 12.19%, P = .036, respectively) and continuously increased after clip removal. Conclusion: The authors’ findings suggest that the hedgehog signaling pathway and its downstream signaling mediator and target GLI1 may play a role in the development and healing process of rotator cuff tendinopathy due to extrinsic rotator cuff impingement. Clinical Relevance: This study suggests the potential for the hedgehog pathway, together with its downstream targets, as candidates for further study as potential therapeutic targets in the treatment of supraspinatus tendinopathy.

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Zoledronic Acid Substantially Improves Bone Microarchitecture and Biomechanical Properties After Rotator Cuff Repair in a Rodent Chronic Defect Model

The American Journal of Sports Medicine ◽

10.1177/0363546520926471 ◽

2020 ◽

Vol 48 (9) ◽

pp. 2151-2160

Author(s):

Jakob E. Schanda ◽

Claudia Keibl ◽

Patrick Heimel ◽

Xavier Monforte ◽

Stefan Tangl ◽

...

Keyword(s):

Zoledronic Acid ◽

Rotator Cuff ◽

Humeral Head ◽

Bone Microarchitecture ◽

Intervention Group ◽

Maximum Load ◽

Biomechanical Properties ◽

Rotator Cuff Tears ◽

Mineral Density ◽

Load To Failure

Background: Bone mineral density at the humeral head is reduced in patients with chronic rotator cuff tears. Bone loss in the humeral head is associated with repair failure after rotator cuff reconstruction. Bisphosphonates (eg, zoledronic acid) increase bone mineral density. Hypothesis: Zoledronic acid improves bone mineral density of the humeral head and biomechanical properties of the enthesis after reconstruction of chronic rotator cuff tears in rats. Study Design: Controlled laboratory study. Methods: A total of 32 male Sprague-Dawley rats underwent unilateral (left) supraspinatus tenotomy with delayed transosseous rotator cuff reconstruction after 3 weeks. All rats were sacrificed 8 weeks after rotator cuff repair. Animals were randomly assigned to 1 of 2 groups. At 1 day after rotator cuff reconstruction, the intervention group was treated with a single subcutaneous dose of zoledronic acid at 100 µg/kg bodyweight, and the control group received 1 mL of subcutaneous saline solution. In 12 animals of each group, micro–computed tomography scans of both shoulders were performed as well as biomechanical testing of the supraspinatus enthesis of both sides. In 4 animals of each group, histological analyses were conducted. Results: In the intervention group, bone volume fraction (bone volume/total volume [BV/TV]) of the operated side was higher at the lateral humeral head ( P = .005) and the medial humeral head ( P = .010) compared with the control group. Trabecular number on the operated side was higher at the lateral humeral head ( P = .004) and the medial humeral head ( P = .001) in the intervention group. Maximum load to failure rates on the operated side were higher in the intervention group ( P < .001). Cortical thickness positively correlated with higher maximum load to failure rates in the intervention group ( r = 0.69; P = .026). Histological assessment revealed increased bone formation in the intervention group. Conclusion: Single-dose therapy of zoledronic acid provided an improvement of bone microarchitecture at the humeral head as well as an increase of maximum load to failure rates after transosseous reconstruction of chronic rotator cuff lesions in rats. Clinical Relevance: Zoledronic acid improves bone microarchitecture as well as biomechanical properties after reconstruction of chronic rotator cuff tears in rodents. These results need to be verified in clinical investigations.

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A Combination Treatment of Raloxifene and Vitamin D Enhances Bone-to-Tendon Healing of the Rotator Cuff in a Rat Model

The American Journal of Sports Medicine ◽

10.1177/0363546520927015 ◽

2020 ◽

Vol 48 (9) ◽

pp. 2161-2169

Author(s):

Dong Min Kim ◽

In Kyoung Shim ◽

Myung Jin Shin ◽

Jae Hee Choi ◽

Yu Na Lee ◽

...

Keyword(s):

Vitamin D ◽

Rotator Cuff ◽

Bone Healing ◽

Rat Model ◽

Combination Treatment ◽

Biomechanical Testing ◽

Female Rats ◽

Muscle Quality ◽

Control Group ◽

The Mean

Background: Tearing and degeneration of the rotator cuff at the tendon-to-bone junction are common in adults aged ≥50 years. Few studies have reported on the relationship between estrogen and the rotator cuff enthesis. In addition to preventing bone loss, selective estrogen receptor modulators have been shown to improve tendon and muscle quality. Purpose: To evaluate the effects of raloxifene (RLX) and vitamin D on rotator cuff tendon-to-bone healing in a rat model. Study Design: Controlled laboratory study. Methods: A total of 29 female rats (58 shoulders) were assigned to 4 groups: (1) control group, (2) ovariectomy (OVX)–only group, (3) no RLX group (OVX and rotator cuff repair [RCR]), and (4) RLX group (OVX, RCR, and RLX). Rats that did not undergo rotator cuff tear (RCT) surgery were divided into the control and OVX-only groups according to OVX surgery. Rats that underwent RCT surgery and RCR were divided into the no RLX and RLX groups according to RLX and vitamin D administration. An estrogen-deficient state was induced by OVX at 12 weeks of age. Bone mineral density (BMD) and trabecular bone characteristics were measured by micro–computed tomography, and healing of the tendon-to-bone junction was evaluated by biomechanical testing, histomorphometry, and micro–magnetic resonance imaging (MRI). Results: The mean final body weight (BW; 461.6 ± 47.3 g) of the OVX-only group was significantly higher and BMD (0.25 ± 0.07 g/cm3) was significantly lower ( P < .001) than the mean final BW (338.5 ± 35.1 g) and BMD (0.48 ± 0.05 g/cm3) of the control group. In contrast, the RLX group showed that the BW (369.6 ± 35.8 g) and BMD (0.41 ± 0.08 g/cm3) were not significantly different from the control group. The RLX group had a significantly higher histomorphometric total score (8.50 ± 1.05) than the no RLX group (4.83 ± 2.48). On biomechanical testing, the RLX group (29.7 ± 9.1 N) showed a significantly higher load to failure than the no RLX group (19.4 ± 8.8 N). On micro-MRI, the RLX group had a more homogeneous low signal and tendon continuity than the no RLX group. Conclusion: The combination treatment of RLX and vitamin D prevented a decrease in local BMD (greater tuberosity of the proximal humerus) and enhanced tendon-to-bone healing of the rotator cuff in a rat model. Clinical Relevance: This study induced an estrogen-deficient state similar to the human postmenopausal state and used drugs that are actually being prescribed in a clinical situation.

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The effectiveness of ramosetron and ondansetron for preventing postoperative nausea and vomiting after arthroscopic rotator cuff repair: a randomized controlled trial

Journal of Orthopaedic Surgery and Research ◽

10.1186/s13018-020-02060-3 ◽

2020 ◽

Vol 15 (1) ◽

Author(s):

Sang-Uk Lee ◽

Hyo-Jin Lee ◽

Yang-Soo Kim

Keyword(s):

Rotator Cuff ◽

Rotator Cuff Repair ◽

Postoperative Nausea And Vomiting ◽

Complete Response ◽

Arthroscopic Rotator Cuff Repair ◽

Control Group ◽

Antiemetic Drug ◽

Arthroscopic Rotator Cuff ◽

Cuff Repair ◽

Rescue Antiemetic

Abstract Background Arthroscopic rotator cuff repair is a painful procedure, and treatment of emetic events associated with drugs used in the current multimodal pain management remains challenging. This study aimed to evaluate the effectiveness of ramosetron or ondansetron to relieve postoperative nausea and vomiting (PONV) and pain after arthroscopic rotator cuff repair. Methods In total, 122 consecutive patients undergoing arthroscopic rotator cuff repair were randomly allocated into three groups: ramosetron group (n = 39), ondansetron group (n = 43), and control group (n = 40). Then, 0.3 mg of ramosetron or 8 mg of ondansetron was administered intravenously at the end of surgery according to group. All patients received general anesthesia and multimodal pain management protocol including preemptive analgesic medication, fentanyl-based intravenous patient-controlled analgesia, and postoperative analgesic medication. Incidence of emetic events, rescue antiemetic requirements (10 mg of metoclopramide, IV), complete response, pain level, and side effects were recorded in three periods: 0–6, 6–24, and 24–48 h postoperatively. The severity of nausea and pain was evaluated using a visual analog scale. Results The ramosetron group tended to have a lower incidence and severity of nausea during the 6- to 24-h postoperative period and fewer rescue antiemetic drug requirements during the 0- to 48-h period than the control group, showing statistical significance. Additionally, the frequency of complete response of the ramosetron and ondansetron groups was significantly higher than that of the control group. No difference was found among the groups in the pain level except during the 0- to 6-h period. The two groups have a higher complete response during the 6- to 24-h period than the control group. Conclusions Ramosetron use led to a lower incidence, mild severity of nausea, and reduced use of rescue antiemetic drug after arthroscopic rotator cuff repair during the 6- to 24-h postoperative period than the control. Level of evidence Level I, randomized controlled trials, treatment study

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Biomechanical Strength of Scaphoid Partial Unions

Journal of Wrist Surgery ◽

10.1055/s-0038-1661362 ◽

2018 ◽

Vol 07 (05) ◽

pp. 399-403 ◽

Cited By ~ 1

Author(s):

Mark Snoddy ◽

Donald Lee ◽

Marc Richard ◽

Mihir Desai ◽

Adam Brekke

Keyword(s):

Failure Mechanism ◽

Clinical Relevance ◽

Permanent Deformation ◽

Maximum Load ◽

Control Group ◽

Average Maximum ◽

Significant Difference ◽

Load To Failure ◽

Biomechanical Strength ◽

Inherent Stability

Background It remains unknown how much force a partially united scaphoid can sustain without refracturing. This is critical in determining when to discontinue immobilization in active individuals. Purpose The purpose of this study was to test the biomechanical strength of simulated partially united scaphoids. We hypothesized that no difference would exist in load-to-failure or failure mechanism in scaphoids with 50% or more bone at the waist versus intact scaphoids. Materials and Methods Forty-one cadaver scaphoids were divided into four groups, three experimental osteotomy groups (25, 50, and 75% of the scaphoid waist) and one control group. Each was subjected to a physiologic cantilever force of 80 to 120 N for 4,000 cycles, followed by load to failure. Permanent deformation during physiologic testing and stiffness, max force, work-to-failure, and failure mechanism during load to failure were recorded. Results All scaphoids survived subfailure conditioning with no significant difference in permanent deformation. Intact scaphoids endured an average maximum load to failure of 334 versus 321, 297, and 342 N for 25, 50, and 75% groups, respectively, with no significant variance. There were no significant differences in stiffness or work to failure between intact, 25, 50, and 75% groups. One specimen from each osteotomy group failed by fracturing through the osteotomy; all others failed near the distal pole loading site. Conclusion All groups behaved similarly under physiologic and load-to-failure testing, suggesting that inherent stability is maintained with at least 25% of the scaphoid waist intact. Clinical Relevance The data provide valuable information regarding partial scaphoid union and supports mobilization once 25% union is achieved.

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