Trochanteric Bursa Is a Source of Connective Tissue Progenitor Cells

Unrepaired Trochanteric Bursae as a Risk Factor for Deep Gluteal Syndrome After Total Hip Arthroplasty: A Prospective Randomized Controlled Trial

BACKGROUND

The trochanteric bursae are often left unrepaired after total hip arthroplasty (THA) and they retract posteriorly over the muscle belly of the piriformis. Deep gluteal syndrome (DGS) is a multifactorial condition presenting as buttock pain and is attributed to nondiscogenic sciatic nerve irritation or impingement causes. The purpose of this study was to investigate the relationship between bursal repair and incidence of DGS in patients undergoing THA.

METHODS

This prospective randomized trial included patients treated with a THA between January and December 2022 for a diagnosis of primary osteoarthritis. Patients were randomized into 2 groups: group 1 underwent a routine bursal repair, while group 2 did not, leaving the bursae unrepaired. Follow-up was performed on the 15th, 30th, and 90th day postoperatively with clinical scores, physical examinations, and laboratory tests. In this cohort of 104 patients, mean age was 55 years (range, 26 to 88). Demographic variables as well as range of motion and overall clinical results showed no significant difference between the groups.

RESULTS

DGS rates were significantly more common in the patients who had an unrepaired bursa (group 2) both on the 30th and 90th postoperative days, while comparison of lateral trochanteric pain on palpation showed similar results between the groups.

CONCLUSIONS

DGS is common in individuals who have unrepaired trochanteric bursal tissue following a THA. Despite its higher frequency, these symptoms did not have a substantial impact on the overall clinical scores, which remained consistent across the study groups.

Activated Serum Increases In Vitro Cellular Proliferation and Growth Factor Expression of Musculoskeletal Cells

The purpose of this study was to investigate proteomic alteration that occurs to whole blood when converted to activated serum (AS) using an autologous thrombin system. This study further sought to evaluate the functional in vitro effect of AS on tenocytes, chondrocytes, subacromial bursal cells, and osteoblasts. The peptide/protein composition of AS was analyzed by liquid chromatography−mass spectrophotometry (LC-MS). The cell lines were treated with AS, and cellular proliferation was quantified 48 h after treatment. Platelet-derived growth factor (PDGF), insulin-like growth factor 1 (IGF-1), vascular endothelial growth factor (VEGF), interleukin-1 beta (IL-1β), and interleukin-1 receptor antagonist (IL-1Ra) were quantified utilizing enzyme-linked immunosorbent assays (ELISAs). LC-MS identified 357 proteins across the AS and whole blood. Fifty-four of the proteins identified had significant differences between the relative protein abundance of the AS samples compared to whole blood. Treatment with AS in all cell lines significantly increased proliferation compared to control cells at 48 h. Increased PDGF, VEGF, and IGF-1 in all cell lines exposed to AS compared to the control (p < 0.05) were observed. These findings suggest that treatment with AS increases in vitro cellular proliferation and the release of growth factors that may play a role in tissue repair.