Arthroscopic treatment of chronic anterior instability of the shoulder in Marfan's syndrome

Radiofrequency in arthroscopic shoulder surgery: a systematic review

BACKGROUND

Radiofrequency has seen an increase in use in orthopedics including cartilage lesion debridement in the hip and knee as well as many applications in arthroscopic shoulder surgery. The purpose of this systematic review is to evaluate the safety and usage of radiofrequency in the shoulder.

METHODS

This systematic review was registered with PROSPERO (international registry) and followed the preferred reporting items for systematic review and meta-analysis protocols (PRISMA-P) guidelines. Embase and PubMed were searched using: "shoulder," "rotator cuff," "biceps," "acromion" AND "monopolar," "bipolar," "ablation," "coblation," and "radiofrequency ablation." The title and abstract review were performed independently. Any discrepancies were addressed through open discussion.

RESULTS

A total of 63 studies were included. Radiofrequency is currently utilized in impingement syndrome, fracture fixation, instability, nerve injury, adhesive capsulitis, postoperative stiffness, and rotator cuff disease. Adverse events, namely superficial burns, are limited to case reports and case series, with higher-level evidence demonstrating safe use when used below the temperature threshold. Bipolar radiofrequency may decrease operative time and decrease the cost per case.

CONCLUSIONS

Shoulder radiofrequency has a wide scope of application in various shoulder pathologies. Shoulder radiofrequency is safe; however, requires practitioners to be cognizant of the potential for thermal burn injuries. Bipolar radiofrequency may represent a more efficacious and economic treatment modality. Safety precautions have been executed by institutions to cut down patient complications from shoulder radiofrequency. Future research is required to determine what measures can be taken to further minimize the risk of thermal burns.

Hyperkyphosis is not dependent on bone mass and quality in the mouse model of Marfan syndrome

Marfan syndrome (MFS) is an autosomal dominant disease affecting cardiovascular, ocular and skeletal systems. It is caused by mutations in the fibrillin-1 (FBN1) gene, leading to structural defects of connective tissue and increased activation of TGF-β. Angiotensin II (ang-II) is involved in TGF-β activity and in bone mass regulation. Inhibition of TGF-β signaling by blockage of the ang-II receptor 1 (AT1R) via losartan administration leads to improvement of cardiovascular and pulmonary phenotypes, but has no effect on skeletal phenotype in the haploinsufficient mouse model of MFS mg^R, suggesting a distinct mechanism of pathogenesis in the skeletal system. Here we characterized the skeletal phenotypes of the dominant-negative model for MFS mgΔ^lpn and tested the effect of inhibition of ang-II signaling in improving those phenotypes. As previously shown, heterozygous mice present hyperkyphosis, however we now show that only males also present osteopenia. Inhibition of ang-II production by ramipril minimized the kyphotic deformity, but had no effect on bone microstructure in male mutant animals. Histological analysis revealed increased thickness of the anterior longitudinal ligament (ALL) of the spine in mutant animals (25.8 ± 6.3 vs. 29.7 ± 7.7 μm), coupled with a reduction in type I (164.1 ± 8.7 vs. 139.0 ± 4.4) and increase in type III (86.5 ± 10.2 vs. 140.4 ± 5.6) collagen in the extracellular matrix of this ligament. In addition, we identified in the MFS mice alterations in the erector spinae muscles which presented thinner muscle fibers (1035.0 ± 420.6 vs. 655.6 ± 239.5 μm²) surrounded by increased area of connective tissue (58.17 ± 6.52 vs. 105.0 ± 44.54 μm²). Interestingly, these phenotypes were ameliorated by ramipril treatment. Our results reveal a sex-dependency of bone phenotype in MFS, where females do not present alterations in bone microstructure. More importantly, they indicate that hyperkyphosis is not a result of osteopenia in the MFS mouse model, and suggest that incompetent spine ligaments and muscles are responsible for the development of that phenotype.

Modified Broström Procedure for Chronic Lateral Ankle Instability in Patients With Generalized Joint Laxity

BACKGROUND

Generalized joint laxity (GJL) has been considered a risk factor for late failure of ligament reconstruction in the knee; however, it is not known whether GJL is the cause of recurrent instability after the modified Broström procedure for chronic lateral ankle instability.

PURPOSE

To compare the clinical results of the modified Broström procedure for chronic lateral ankle instability in patients with or without GJL.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

A total of 100 patients (100 ankles) who underwent the modified Broström procedure were divided into 2 groups, with or without GJL, according to the Beighton criteria. Age and body mass index were matched between the 2 groups. The mean follow-up duration was 43.3 months in the laxity group (44 ankles; Beighton score ≥5) and 42.9 months in the nonlaxity group (56 ankles).

RESULTS

The mean preoperative Karlsson and American Orthopaedic Foot and Ankle Society (AOFAS) scores were a respective 53.2 and 60.9 in the laxity group and 53.9 and 62.6 in the nonlaxity group, and these scores improved to 87.4 and 89.5, respectively, in the laxity group and to 94.1 and 94.8, respectively, in the nonlaxity group at final follow-up. The mean preoperative talar tilt angle and anterior talar translation were a respective 12.5° and 8.8 mm in the laxity group and 10.8° and 8.5 mm in the nonlaxity group, and these values improved to 7.3° and 6.0 mm, respectively, in the laxity group and to 5.2° and 5.0 mm, respectively, in the nonlaxity group at final follow-up. Failure rates were 11.4% (5 patients) in the laxity group and 1.8% (1 patient) in the nonlaxity group. Significant differences were found between the 2 groups in terms of the Karlsson score, AOFAS score, talar tilt angle, anterior talar translation, and failure rate at final follow-up (P < .05).

CONCLUSION

Patients with GJL showed inferior outcomes and a higher failure rate compared with patients without GJL. Therefore, GJL appears to be a risk factor associated with recurrent instability after the modified Broström procedure.