Acetabular Labral Repair and Selective Labral Debridement Show No Significant Difference in Clinical Outcomes at a Minimum 2-Year Follow-Up.

PURPOSE: To compare the outcomes of arthroscopic labral repair using looped type suture with a matched-pair selective labral debridement with a minimum 2-years follow-up. METHODS: We identified 378 patients undergoing primary arthroscopic labral repair using loop-suture and selective labral debridement from January 2, 2018, to December 28, 2020. The labral repair group was matched 1:1 to a selective labral debridement control group by age, sex, body mass index, follow-up period, lateral center-edge angle, Tönnis grade, and preoperative joint space. Before surgery, 3-Tesla radial magnetic resonance imaging with a 3-dimensional double-echo steady-state sequence was obtained following failed nonoperative treatment lasting more than 3 months. Follow-up imaging was conducted at a minimum of 2 years. In both groups, the ratio of positive slices in which a disrupted chondrolabral junction was observed between the 2 o'clock and 11 o'clock positions was measured. Patient-reported outcome scores included the Harris Hip Score, visual analog score, Hip Outcome Score Activities of Daily Living Subscale, and Hip Outcome Score of Sport-Specific Subscale. RESULTS: In total, 76 patients of the repair group were matched to 76 controls with a minimum 2-years follow-up (repair vs control: 2.6 ± 0.4 vs 2.6 ± 0.4 years, P = .775). The repair group experienced a 2-fold improvement (0.6 ± 0.1 to 0.3 ± 0.1, P＜.001). Although the selective debridement group experienced a 3-fold improvement (0.3 ± 0.1 to 0.1 ± 0.1, P＜.001). Significant improvement of the patient-reported outcome was shown in both groups at final follow-up without significant difference between the 2 groups. CONCLUSIONS: The mid-term clinical outcomes are comparable between the labral repair using looped type suture and selective labral debridement group. Although a gap between the labrum and articular cartilage may appear in 3-dimensional double-echo steady-state magnetic resonance imaging results after labral repair, it does not correspond with clinical outcomes. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Tissue Regrowth and Its Vascularization Through Bone Marrow Stimulation: Microfracture at the Acetabular Rim for Irreparable Labral Tear in a Porcine Model.

BACKGROUND: The treatment of irreparable acetabular labral tear remains a great challenge. Whether fibrocartilage-like tissue can regrow with sufficient volume to fill the labral defect area through bone marrow stimulation remains unknown. PURPOSE: To characterize the healing process and vascularization course of the regrown tissue after microfracture at the acetabular rim for irreparable labral tears in a porcine model. STUDY DESIGN: Descriptive laboratory study. METHODS: Twelve pigs randomly underwent unilateral microfracture at the acetabular rim after the resection of a 10 mm-long section of labrum from 10 to 1 o'clock. Pigs were randomly sacrificed at 6 and 12 weeks postoperatively. The regrown tissues were harvested for macroscopic evaluation and histologic assessment. The regrown tissue was zoned into 2 halves to observe the vascular distribution: the capsular half (zone I) and the articular half (zone II). Each zone was divided into 2 parts: the peripheral part (IA and IIA) and the part attached to the acetabulum (IB and IIB). RESULTS: At 6 weeks, all regrown tissue was hypotrophic with <50% filling of the labral defect. Fibrochondrocytes were concentrated at the interface between the acetabulum and the regrown tissue. The vascularization was equal among each part within the regrown tissue. As compared with regrown tissue at 12 weeks, proteoglycan and collagen type 1 and 2 were more evident within the regrown tissue at 6 weeks. At 12 weeks, tissue disintegration occurred in all regrown tissue with <25% filling of the labral defect area. The vascular structure could barely be observed, with few fibrochondrocytes found at the area adjacent to the acetabulum. CONCLUSION: Fibrocartilage-like tissue did regrow with well-distributed vascular ingrowth of each part of the regrown tissue through bone marrow stimulation at the early stage. However, insufficient volume of the regrown tissue led to loss of the hip suction seal and subsequent tissue disintegration. CLINICAL RELEVANCE: Microfracture at the rim of the acetabulum alone could not restore the morphology and function of the acetabular labrum. Nonetheless, microfracture at the acetabular rim might be a viable adjunct to labral reconstruction, as the well-distributed vascularization through bone marrow stimulation might overcome the obstacle of poor vascular ingrowth of the articular half of the autograft.

Tissue Integration and Chondroprotective Potential of Acetabular Labral Augmentation with Autograft Tendon: Study of a Porcine Model.

BACKGROUND: The aim of this study was to explore the tissue healing process and changes in articular cartilage following acetabular labral augmentation in a porcine model. METHODS: The labrum was resected unilaterally from 10 o'clock to 1 o'clock on the capsular side in 36 pigs. Eighteen pigs underwent labral augmentation (AUG group) using autologous Achilles tendon. No additional procedures were performed in the remaining pigs (control group). The pigs were killed at 6, 12, or 24 weeks postoperatively for histological assessment and measurement of the inflammatory cytokines interleukin (IL)-6, IL-1ß, and tumor necrosis factor (TNF)-α in synovial fluid. RESULTS: All autografts were well placed in the labral defect in the AUG group, and good integration of the autograft with the remnant chondrolabral junction was observed at 24 weeks; only scar tissue was observed in the control group at 6, 12, and 24 weeks. Fibrochondrocytes were concentrated at the transition between the autograft and native labrum at early time points, and the cells within the autograft labrum were predominantly fibrochondrocytes at 24 weeks. Rough and irregular articular cartilage surfaces were observed in 3 of the 6 samples in the AUG group at 24 weeks; the others appeared smooth. Focal cartilage erosion (predominantly in the acetabulum) occurred in all samples in the control group at 12 and 24 weeks. The Mankin score at 24 weeks was significantly lower in the AUG group than in the control group (mean [95% confidence interval]: 2.33 [1.06 to 3.6] versus 9 [8.06 to 9.94], p < 0.001). Likewise, the concentrations of all cytokines (in pg/mL) were significantly lower in the AUG group than in the control group at 24 weeks (IL-6: 166.6 [155.22 to 177.94] versus 245.9 [242.66 to 249.14], p < 0.001; IL-1ß: 122.1 [116.4 to 127.83] versus 282.9 [280.29 to 285.51], p < 0.001; and TNF-α: 56.22 [53.15 to 59.29] versus 135 [131.66 to 138.24], p < 0.001). CONCLUSIONS: Autograft tendon used for labral augmentation was able to integrate well with the native labrum, which may help to preserve the articular cartilage. CLINICAL RELEVANCE: Labral augmentation with autograft tendon may be a feasible option in cases of viable labral remnants.

The Vascularization Course of Labral Autograft and Its Effect on Tissue Healing: Acetabular Labral Augmentation Versus Labral Reconstruction in a Porcine Model.

BACKGROUND: The preservation of the native labral vascularization is assumed to be the potential advantage of acetabular labral augmentation, the effect of which remains unknown. PURPOSE: To identify the vascular distribution within the labral autograft and its effect on the healing process between labral augmentation (AUG) and reconstruction (RECON) in a porcine model. STUDY DESIGN: Controlled laboratory study. METHODS: A total of 36 pigs randomly underwent unilateral labral augmentation or reconstruction (AUG group, n = 18; RECON group, n = 18). The pigs were randomly sacrificed at 6, 12, and 24 weeks postoperatively. The labral autografts were harvested for macroscopic evaluation and histologic assessment. The labral autograft was zoned into 2 halves to observe the vascular distribution: the capsular half (zone I) and the articular half (zone II). Each zone was divided into 2 parts: the peripheral part (IA and IIA) and the part attached to the acetabulum (IB and IIB). RESULTS: At 6 weeks, there existed more vascular ingrowth in zone I, whereas zone IIB appeared nearly avascular in both groups. At 12 weeks, the area with the greatest vascularity was zone II in the RECON group and zone IA in the AUG group. The vascularity was concentrated at zones IA and IIA in both groups at 24 weeks. The labral autografts were hypertrophic with sufficient filling of the labral defect in both groups at 6 weeks. At 12 weeks, an insufficient volume of the articular half was observed in 3 of 6 labral autografts in the RECON group, while all autografts remained well integrated with the chondrolabral junction in the AUG group. At 24 weeks, unsatisfactory merging of the labral autograft with the cartilage at the articular side was found in 2 of 6 labral autografts in the RECON group, which was not observed in the AUG group despite the sufficient volume of autografts labrum in both groups. CONCLUSION: Slow vascular ingrowth within the articular half might account for the poor healing of the reconstructed labral autograft. Labral augmentation provides the possibility of better tissue healing because of the preservation of the original chondrolabral junction compared with labral reconstruction. CLINICAL RELEVANCE: Labral augmentation might be a feasible alternative to labral reconstruction under the condition of viable labral remnants.

Mixed bacterial-fungal infection following total hip arthroplasty: A case report.

Prosthetic infection is one of the severe postoperative complications of arthroplasty. Mixed bacterial-fungal prosthetic infection is rare but can be disastrous. This case was a 76-year-old female suffered from prosthetic infection following total hip replacement due to femoral neck fracture and underwent multiple debridements. The culture of periprosthetic tissue was bacteriologically sterile following the first debridement, while the Staphylococcus hominis was identified in the second debridement in the previous hospitalization where fungal infection had not been considered. Thus the pathogen spectrum of anti-infection therapy failed to contain fungus. Ultimately, the culture result of our sampled periprosthetic tissue during the third debridement was Candida albicans without bacterium in our hospital. The fungal prosthetic infection was successfully treated by a two-stage revision with antifungal drugs. Accurate diagnosis and standardized treatment is the key to the therapy of infection after hip arthroplasty, especially for mixed bacterial-fungal prosthetic infection.

Microfracture of Acetabular Rim After Segmental Labral Resection to Restore the Morphology and Function of Labrum: A Retrospective Study of More than 2 Years Follow-up.

OBJECTIVE: To report on the clinical outcome of patients undergoing combined arthroscopic treatment of labral resection and microfracture at the rim of acetabulum at a minimum 2-year follow-up. METHODS: The retrospective study included 38 patients undergoing hip arthroscopy for irreparable labral injury from 24 February 2014 to 26 February 2018. Thirteen patients were excluded owing to patient refusal of participation and concomitant diseases like synovial chondromatosis and dysplasia hip. The study group consisted of patients undergoing combined arthroscopic labral resection and microfracture at the rim of acetabulum (MICRO Group: 20 patients), arthroscopic labral resection alone (RESEC Group: five patients). Postoperative three-dimensional (3D) double-echo steady-state (DESS) sequence with radial imaging at 3 Tesla were obtained and fluoroscopic image of the involved hip under distraction were used to observe the restoration of vacuum effect. Patient-reported outcome scores (PROs) including the Harris Hip Score (HHS), Visual Analogue Score (VAS), Hip Outcome Score Activities of Daily Living Subscale (HOS-ADL), Hip Outcome Score Sport-Specific Subscale (HOS-SSS) were collected and compared between two groups. RESULTS: All patients were followed up for at least 6 months. The follow-up time of RESEC group is longer than MICRO group (46.6 months vs 23.9 months, P < 0.05). The 3D DESS imaging demonstrated intermediate signal intensity at the relative area where the labrum resected followed by microfracture at the acetabular rim in MICRO group. Meanwhile, regrowth of labrum-like tissue was not observed in MRI imaging of the RESEC group. Furthermore, vacuum effect was more apparent in MICRO group compared with RESEC group. All PROs in both groups showed a statistically significant improvement at follow-up compared with preoperative levels. RESEC group: HHS (73.0 vs 93.8, P < 0.05); HOS-ADL (51.5 vs 89.1, P < 0.05); HOS-SSS (47.8 vs 88.3, P < 0.05); VAS (6.4 vs 2.0, P < 0.05). MICRO group: HHS (70.5 vs 91.5, P < 0.05); HOS-ADL (52.4 vs 87.0, P < 0.05); HOS-SSS (48.1 vs 86.5, P < 0.05); VAS (6.3 vs 1.6, P < 0.05). One patient of MICRO group had transient neurapraxias of the pudendal nerve that resolved completely by 3 months. There showed no statistically significant difference between groups regarding the preoperative and postoperative PROs. CONCLUSION: Compared to labral resection, combined arthroscopic labral resection and microfracture at the rim of acetabulum is able to fulfill the labral defect area with the potential to restore the seal effect of labrum as an effective and safe option for irreparable segmental labral tears.

Diagnosis and treatment of labral tear.

OBJECTIVE: To review the literature regarding diagnosis and treatment of labral tear. DATA SOURCES: A systematic search was performed in PubMed using various search terms and their combinations including hip, labrum, acetabular labral tear, arthroscopy, diagnosis, and anatomy. STUDY SELECTION: For each included study, information regarding anatomy, function, etiology, diagnosis, and management of acetabular labral tear was extracted. RESULTS: Five hundred and sixty abstracts about anatomy, function, etiology, diagnosis, and management of acetabular labral tear were reviewed and 66 selected for full-text review. The mechanism of labral tear has been well explained while the long-term outcomes of various treatment remains unknown. CONCLUSIONS: Labral tear is generally secondary to femoroacetabular impingement, trauma, dysplasia, capsular laxity, and degeneration. Patients with labral tear complain about anterior hip or groin pain most commonly with a most consistent physical examination called positive anterior hip impingement test. Magnetic resonance arthrography is a reliable radiographic examination with arthroscopy being the gold standard. Conservative treatment consists of rest, non-steroidal anti-inflammatory medication, pain medications, modification of activities, physical therapy, and intra-articular injection. When fail to respond to conservative treatment, surgical treatment including labral debridement, labral repair, and labral reconstruction is often indicated.