Rotator cuff anchor repair: Histological changes associated with the recovering mechanical properties in a rabbit model

Rotator cuff tears result in shoulder pain, stiffness, weakness and loss of motion. After surgical repair, high failure rates have been reported based on objective imaging and it is recognized that current surgical treatments need improvement. The aim of the study was to assess whether implants composed of freeze-dried chitosan (CS) solubilized in autologous platelet-rich plasma (PRP) can improve rotator cuff repair in a rabbit model. Complete tears were created bilaterally in the supraspinatus tendon of New Zealand White rabbits ( n = 4 in a pilot feasibility study followed by n = 13 in a larger efficacy study), which were repaired using transosseous suturing. On the treated side, CS-PRP implants were injected into the transosseous tunnels and the tendon itself, and healing was assessed histologically at time points ranging from one day to two months post-surgery. CS-PRP implants were resident within transosseous tunnels and adhered to tendon surfaces at one day post-surgery and induced recruitment of polymorphonuclear cells from 1 to 14 days. CS-PRP implants improved attachment of the supraspinatus tendon to the humeral head through increased bone remodelling at the greater tuberosity and also inhibited heterotopic ossification of the supraspinatus tendon at two months. In addition, the implants did not induce any detectable deleterious effects. This preliminary study provides the first evidence that CS-PRP implants could be effective in improving rotator cuff tendon attachment in a small animal model.

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Nonabsorbable-Suture-Induced Osteomyelitis: A Case Report and Review of the Literature

Case Reports in Orthopedics ◽

10.1155/2012/381490 ◽

2012 ◽

Vol 2012 ◽

pp. 1-3

Author(s):

Cheng Hong Yeo ◽

Nick C. Russell ◽

Tom Sharpe

Keyword(s):

Mechanical Properties ◽

Rotator Cuff ◽

Rotator Cuff Repair ◽

Proximal Humerus ◽

Deep Infection ◽

Absorbable Suture ◽

Review Of The Literature ◽

Nonabsorbable Suture ◽

Cuff Repair ◽

Anchor Suture

We are reporting a case of nonabsorbable suture-induced osteomyelitis in patient who had an open rotator cuff repair with nonabsorbable Ethibond anchor suture. Patient in this case presented with very subtle clinical features of osteomyelitis of the left proximal humerus 15 years after initial rotator cuff repair surgery. Literature had shown that deep infection following rotator cuff repairs, although rare, can be easily missed and can cause severe complications. Absorbable suture had been demonstrated to be more superior, in terms of rate of deep infection, as compared to nonabsorbable suture when used in rotator cuff repair surgery. Both absorbable and nonabsorbable suture had been demonstrated to have similar mechanical properties by several different studies. The case demonstrated that initial presentation of deep infection can be subtle and easily missed by clinicians and leads to further complications.

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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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Volumetric MicroCT Intensity Histograms of Fatty Infiltration Correlate with the Mechanical Strength of Rotator Cuff Repairs: An Ex Vivo Rabbit Model

Clinical Orthopaedics and Related Research ◽

10.1097/corr.0000000000001540 ◽

2020 ◽

Vol Publish Ahead of Print ◽

Author(s):

Phillip E. McClellan ◽

Lekha Kesavan ◽

Yujing Wen ◽

Jason Ina ◽

Derrick M. Knapik ◽

...

Keyword(s):

Rotator Cuff ◽

Mechanical Strength ◽

Ex Vivo ◽

Fatty Infiltration ◽

Rabbit Model

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Enhanced Tendon-to-Bone Healing of Chronic Rotator Cuff Tears by Bone Marrow Aspirate Concentrate in a Rabbit Model

Clinics in Orthopedic Surgery ◽

10.4055/cios.2018.10.1.99 ◽

2018 ◽

Vol 10 (1) ◽

pp. 99 ◽

Cited By ~ 15

Author(s):

Xiao Ning Liu ◽

Cheol-Jung Yang ◽

Ji Eui Kim ◽

Zhen Wu Du ◽

Ming Ren ◽

...

Keyword(s):

Bone Marrow ◽

Rotator Cuff ◽

Bone Healing ◽

Bone Marrow Aspirate ◽

Rabbit Model ◽

Rotator Cuff Tears ◽

Bone Marrow Aspirate Concentrate

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Effects of Allogenic Dermal Fibroblasts on Rotator Cuff Healing in a Rabbit Model of Chronic Tear

The American Journal of Sports Medicine ◽

10.1177/0363546518770428 ◽

2018 ◽

Vol 46 (8) ◽

pp. 1901-1908 ◽

Cited By ~ 9

Author(s):

Jieun Kwon ◽

Yun Hee Kim ◽

Sung-Min Rhee ◽

Tae In Kim ◽

Jimin Lee ◽

...

Keyword(s):

Rotator Cuff ◽

Laboratory Study ◽

Bone Healing ◽

Rabbit Model ◽

Dermal Fibroblasts ◽

The Other ◽

Histological Evaluation ◽

Load To Failure ◽

Group A ◽

Group B

Background: The failure of rotator cuffs to heal after repair is an unresolved surgical issue. There have been substantial efforts, including the use of biological supplements, to enhance tendon healing. Dermal fibroblasts are a good candidate for tendon tissue engineering because they are similar to the tenocytes used for collagen synthesis. In addition, they are easily accessible because autologous dermal fibroblasts can be obtained from individual skin without major skin defects and allogenic dermal fibroblasts (ADFs) have already been commercialized in the field of skin engineering. Purpose: To determine the effects of dermal fibroblasts on tendon-to-bone healing in a rabbit model of a chronic rotator cuff tear. Study Design: Controlled laboratory study. Methods: A total of 33 rabbits were randomly allocated into 3 groups (n = 11 each). Supraspinatus tendons were detached and left for 6 weeks to establish a chronic rotator tear model. Torn tendons were repaired in a transosseous manner with the injection of 5 × 106 ADFs with fibrin in group A, fibrin only in group B, and saline only in group C. At 12 weeks after repair, the mechanical test and histological evaluation were performed. Results: Seven rabbits died before the evaluation (1 in group A, 2 in group B, 4 in group C). In the final evaluation, the mean ± SD load to failure was 48.1 ± 13.3 N/kg for group A, 34.5 ± 8.9 N/kg for group B, and 31.1 ± 8.3 N/kg for group C, and group A showed significantly higher load-to-failure values than the other groups ( P = .011). The midsubstance tear rate, which presented stronger tendon-to-bone healing than insertional tear, was 50.0% in group A, 22.2% in group B, 28.6% in group C, but the differences were not statistically significant ( P = .413). In the histological evaluation, group A showed greater collagen fiber continuity and better orientation than the other groups. Conclusion: This controlled laboratory study verified, on the basis of biomechanics and histology, the potential for the use of ADFs in rotator cuff healing. The current results suggest a new biological supplement to increase the rate of rotator cuff healing. Clinical Relevance: The most important finding of this study was the potential for a new biological supplement to enhance rotator cuff healing—a continuing challenge.

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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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