Intrasynovial autograft for reconstruction of chronic large rotator cuff tears in a rabbit model: biomechanical, computed tomography, and histological results.

BACKGROUND: Rotator cuff (RC) tears are a common cause of shoulder dysfunction and pain, posing significant challenges for orthopedic surgeons. Grafts have been proposed as a solution to augment or bridge torn tendons, but optimal clinical outcomes are not always achieved due to poor graft integration, suboptimal mechanical properties, and immunological reactions. The aim of this study was to investigate the biomechanical, CT and histological results of RC reconstruction using an intrasynovial tendon autograft, in a chronic large tear subscapularis rabbit model. METHODS: Twenty-six adult male Zealand white rabbits were used in this study. Large defects in the subscapularis tendons were produced bilaterally in 20 rabbits. After 6 weeks, secondary procedures were performed to the right shoulder of the rabbits, which were reconstructed with an intrasynovial interposition autograft (graft group). The left shoulder did not undergo any further treatment (defect group). The specimens were randomly divided into two equal time groups and underwent biomechanical testing, CT analysis, and histological evaluation at 6, and 12 weeks after reconstruction. In addition, 6 rabbits that were not operated, were used as a control group. RESULTS: At 12 weeks post-repair, the graft group exhibited a significant increase in ultimate failure load compared to the defect group (p < 0.05). Furthermore, the 12-week graft group demonstrated comparable stiffness to that of the control group. CT analysis indicated no significant progression of intramuscular fat accumulation in both graft groups, in contrast to the 12-week defect group when compared to the control group. Finally, histological evaluation revealed a gradual integration of the graft with the host tissue at 12 weeks. CONCLUSION: Our study suggests that intrasynovial flexor tendon autografts hold promise as an effective interposition graft for the reconstruction of chronic large RC tears, as they improve the biomechanical and biological properties of the repaired tendon. Nonetheless, further investigations in preclinical large animal models are warranted to validate and extrapolate these findings to human studies.

Repair of chronic and large rotator cuff tears using extra-synovial autografts: An experimental study in rabbits.

Purpose: To investigate whether and how extra-synovial autografts can enhance the reconstruction of chronic and large rotator cuff tears in a rabbit subscapularis model. Methods: Twenty rabbits were used to create a large subscapularis tear bilaterally. Six weeks later, the right shoulder of each rabbit was operated to repair the tear with an extra-synovial autograft, whereas the left shoulder did not undergo any surgery. At 6 and 12 weeks after the second procedure, the specimens underwent biomechanical and histological evaluation. Six more rabbits were used only as a normal reference. Results: Biomechanical evaluation demonstrated that the ultimate load to failure of the Graft group (184.1 ± 35.7 N) was significantly higher (p = 0.04) than that of the Defect group (144.5 ± 32.2 N) at 12 weeks after repair, rising to 76% of the normal subscapularis tendon tensile strength. Histological analysis revealed an enhanced healing environment with neoangiogenesis and decreased inflammatory response at the repair site. Moreover, the tendon maturing score of the Graft group increased substantially from 6 (15.8 ± 0.9) to 12 (23.1 ± 0.6) weeks after repair (p = 0.01). Conclusion: In vivo data support the efficacy of extra-synovial autograft interposition in repairing chronic and large rotator cuff tears in a rabbit subscapularis model. The autografts were capable of enhancing the biomechanical properties of the repaired tendons, as evidenced by increased tensile strength, and forming new connective tissue simulating a fibrocartilage zone, as revealed by histological evaluation. Level of Evidence: N/A.

The Influence of Smoking on Healing of Scaphoid Non-union after a Vascularized Pedicle Bone Flap Operation: A Review and Meta-analysis.

Background: The purpose of this study is to compare the vascularized bone flaps (VBF) that are used in operations for scaphoid non-union in smokers and non-smokers and to scrutinize if the better biological potential of the VBFs can counteract the negative influence of smoking on healing. Materials and Methods: Our study included articles published until 2016, with scaphoid non-union patients who were operated on with a VBF or a VBG. Results: Eighteen articles met eligibility criteria with 335 non-smokers and 136 smokers totally. Healing of the scaphoid non-union was significantly more probable in the non-smoking group (OR=5.54, p<0.001). Patients with avascular necrosis in the proximal pole of the scaphoid (AVNPP) and non-AVNPP showed that non-smoking favors a better healing rate in both of these subgroups (p<0.001 and p<0.001, respectively). Non-smokers have 11 times and the non-AVNPP patient's 7.7 times greater probability of healing of the non-union. Meta-analysis of the data for time for healing showed a longer time in the smokers' group by 2.46 weeks, though non-statistically significant. The analysis could not prove that smoking is a predisposing factor for the development of AVNPP (spearman=0.094, p<0.05). Despite that, preoperative smoking cessation proved to be an inadequate healing moderator (OR=3.5, p=0.268). Finally, VBFs showed a significantly better healing rate compared with nVBGs in smokers (p=0.001). Conclusions: A hand surgeon should always take into consideration that smoking negatively influences the healing potential of a scaphoid non-union despite the theoretically superior biological background that VBFs offer. In patients who refuse to quit smoking, a VBF may be considered a better choice than a conventional graft.

The Influence of Smoking on Healing of Scaphoid Non-union after a Vascularized Pedicle Bone Flap Operation: A Review and Meta-analysis.

Background: The purpose of this study is to compare the vascularized bone flaps (VBF) that are used in operations for scaphoid non-union in smokers and non-smokers and to scrutinize if the better biological potential of the VBFs can counteract the negative influence of smoking on healing. Materials and Methods: Our study included articles published until 2016, with scaphoid non-union patients who were operated on with a VBF or a VBG. Results: Eighteen articles met eligibility criteria with 335 non-smokers and 136 smokers totally. Healing of the scaphoid non-union was significantly more probable in the non-smoking group (OR=5.54, p<0.001). Patients with avascular necrosis in the proximal pole of the scaphoid (AVNPP) and non-AVNPP showed that non-smoking favors a better healing rate in both of these subgroups (p<0.001 and p<0.001, respectively). Non-smokers have 11 times and the non-AVNPP patient's 7.7 times greater probability of healing of the non-union. Meta-analysis of the data for time for healing showed a longer time in the smokers' group by 2.46 weeks, though non-statistically significant. The analysis could not prove that smoking is a predisposing factor for the development of AVNPP (spearman=0.094, p<0.05). Despite that, preoperative smoking cessation proved to be an inadequate healing moderator (OR=3.5, p=0.268). Finally, VBFs showed a significantly better healing rate compared with nVBGs in smokers (p=0.001). Conclusions: A hand surgeon should always take into consideration that smoking negatively influences the healing potential of a scaphoid non-union despite the theoretically superior biological background that VBFs offer. In patients who refuse to quit smoking, a VBF may be considered a better choice than a conventional graft.

Does early repair of traumatic rotator cuff tears provide better outcomes? A systematic review.

Our aim was to systematically review literature of trauma related rotator cuff tears in order to evaluate the outcome and healing integrity in relation to time of surgery. Our research question was whether earlier surgical repair leads to superior functional results. This review was conducted according to PRISMA statement. A literature search of Pubmed, Embase, Cohrane was conducted, with two researchers assessing studies for eligibility and quality. A total of 20 studies, published between 1980 and 2019, met the inclusion criteria and were divided into two groups based on duration of symptoms before surgery. Group A comprised of studies in which duration was < 3 months and Group B > 3 months. Within each group there was a statistically significant improvement in the CS from pre-operative to post-operative outcome, but the improvement for Group A was statistically higher in comparison to Group B (P=0.01). Nevertheless, there was no significant difference in the final outcome for the two groups (P=0.29). The re-tear rate per 100 patients was calculated 28.5(±7.2) for Group A, and 17.2 (±12.56) for Group B (P=0.056). Our results suggest that functional outcome and tendon healing may not be valid arguments for early surgical repair. Therefore, repair of traumatic RCTs could be recommended whenever technically possible.

A Misguiding Osteoid Osteoma in the Bicipital Tuberosity of the Radius.

Osteoid osteoma is a benign bone tumor that appears most frequently in young patients. It is more common in males and it concerns mostly the long bones of the lower limb. A 20-year-old young woman presented to our outpatient department with pain in her left elbow. The symptoms began four years ago. At first, her symptoms were attributed to ulnar neuritis, confirmed by nerve conduction studies. In the following two years, she had undergone two surgical operations for decompression of the ulnar nerve. As a result, she reported poor results, which forced her to take frequently anti-inflammatory drugs for some years. When the patient presented to us, we planned a three-phase bone scan and an elbow MRI, which revealed the lesion. Based on the image findings of osteoid osteoma, we proceeded to the surgical removal of the tumor. Since then, the patient is pain-free and has a full range of motion of the affected elbow. Osteoid osteoma usually mimics multiple pathologies in the upper limb especially joint disease posing a challenge for the physician. The diagnosis requires high index of suspicion and a prompt diagnostic and surgical management.