Glenoid Bone Reaction to All-Soft Suture Anchors Used for Shoulder Labral Repairs.

BACKGROUND: All-soft suture anchors (ASSAs) are commonly used for shoulder labral repair and capsulorrhaphy in patients with shoulder instability. While these anchors may have some specific advantages over other types of suture anchors, little is known about the prevalence and time-dependence of bone cyst formation and tunnel expansion after implantation of ASSAs. The aim of this study was to quantify the proportions of cyst formation and tunnel expansion around ASSAs and to characterize and test for differences in abnormalities observed at different postoperative time points. METHODS: Thirty patients who were treated with arthroscopic shoulder stabilization surgery with ASSAs (1.4 mm; JuggerKnot, Biomet) underwent a computed tomography (CT) scan of the operatively treated shoulder at 1 month (10 patients), 6 months (10 patients), or 12 months (10 patients) postoperatively. Demographic and operative data were collected, and CT scans were evaluated for cyst formation, tunnel expansion, and tunnel volume measured in cubic millimeters. Statistical analyses were performed to detect differences in these outcomes among the follow-up groups. All shoulders were stable at all time points of the study, and there were no incidents of recurrent instability during the study period. RESULTS: Ninety-one suture anchors were evaluated in 30 patients. Tunnel expansion was identified in the large majority of patients in the 6-month and 12-month follow-up groups, with a significant increase in these proportions compared with the 1-month follow-up group (p = 0.002). Mean tunnel volumes also significantly increased over the study period (p < 0.001). The presence of cyst formation was negligible in all 3 follow-up cohorts. CONCLUSIONS: This study demonstrated low rates of cyst formation but a significantly increased tunnel volume 6 and 12 months after shoulder labral surgery with ASSAs. There was no association with the initial tunnel location. Additional well-controlled studies with longer follow-up are needed to identify potential associations among tunnel expansion, intraoperative technique, and clinical outcomes. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Population frequencies and putative haplotypes of the killer cell immunoglobulin-like receptor sequences and evidence for recombination.

BACKGROUND: The killer cell immunoglobulin-like receptors (KIR) are a family of receptors expressed on natural killer (NK) cells and some T cells. Class I HLA molecules on target cells are the ligands for the KIR receptors. The number of KIR genes has been reported to vary between individuals, resulting in different KIR haplotypes. There is little published data on the frequency of each KIR gene and the linkage disequilibrium between the genes. Because there is evidence that NK cells may be involved in bone marrow transplant rejection, we have determined the KIR gene frequencies and possible haplotypic arrangements by linkage disequilibrium analysis in an Australian population. METHODS: Controls, patients with leukemia, and unrelated bone marrow donor-recipient pairs were typed for the presence of 11 KIR genes by polymerase chain reaction-sequence specific priming. RESULTS: Ninety percent of the population was found to have a sufficient number and variety of KIR genes to detect any mismatch of HLA-A, -B, and -C alleles on NK target cells. The 11 KIR genes could be divided into two groups based on linkage disequilibrium between pairs of genes. Evidence for a recombination within the KIR gene complex is presented. CONCLUSION: Typing for the presence of particular KIR genes may be indicated for bone marrow donor-recipient pairs for whom a class I HLA mismatch is unavoidable.