Accuracy of acetabular cup placement during anterolateral supine total hip arthroplasty using intraoperative fluoroscopy: a retrospective study.

BACKGROUND: In our institution, total hip arthroplasty (THA) is performed using the anterolateral supine (ALS) approach with intraoperative fluoroscopy. This study aimed to investigate and review the accuracy of acetabular cup placement in ALS-THA using intraoperative fluoroscopy. METHODS: A total of 142 patients with 154 joints (mean age 64.3 years, 30 males and 112 females) underwent ALS-THA with intraoperative fluoroscopy at the same institution. The target angle of the cup position was set at 40° for radiographic inclination (RI) and 5°-25° for radiographic anteversion (RA) based on the functional pelvic plane according to the pelvic motion during individual postural changes. The cup position angle was measured using postoperative computed tomography, and the error in the target angle was investigated. RESULTS: The target angle of RI was 40°, and the postoperative RI was 39.3° ± 4.3°. The target angle of the RA was 17° ± 2.6°, and the postoperative RA was 20.6° ± 3.7°. The absolute values of the error from the target angle were 3.6° ± 2.5° for RI and 4.2° ± 3.3° for RA. For RI and RA, 67.5% (104/154 joints) were within ± 5° of the target and 96.1% (148/154 joints) were within ± 10°. CONCLUSIONS: The accuracy of cup positioning in ALS-THA using intraoperative fluoroscopy was good and appeared comparable to that of various navigation systems.

MRI Findings of Muscle Damage after Total Hip Arthroplasty Using the Complete Muscle Preserving Anterolateral Supine Approach.

Background and Objectives: We performed anterolateral total hip arthroplasty (ALS THA) with the purpose of complete muscle-tendon preservation without muscle-tendon dissection. This study aimed to evaluate muscle damage in the periprosthetic hip joint muscles of patients undergoing ALS THA at 1-year post-operative hip magnetic resonance imaging (MRI). Materials and Methods: We evaluated changes in the muscle cross-sectional area (M-CSA) and fatty atrophy of the periprosthetic muscles. We also assessed the Harris hip score on pre-operative and 12-month post-operative MRI in 66 patients who underwent ALS THA. The grade of M-CSA atrophy was classified into no atrophy, slight atrophy, moderate atrophy, and severe atrophy. Fatty atrophy was classified as improved, no change, and worsened using the Goutallier classification. Results: More than 90% of patients' M-CSA had no atrophy in the obturator internus (Oi), obturator externus (Oe), gluteus medius (Gmed), and gluteus minimus (Gmin), and some improvement was observed in terms of fatty atrophy. In contrast, M-CSA of the tensor fascia latae (TFL) muscle was clearly decreased, and there was no improvement in the TFL fatty atrophy. However, the presence or absence of TFL atrophy did not affect clinical outcome. Conclusions: We performed the complete muscle preserving procedure, ALS THA, with attention to preserving the Oi and Oe by direct visual confirmation and gentle treatment of the Gmed and Gmin with effective retraction. Post-operative M-CSA atrophy evaluation on MRI showed that the Oi, Oe, Gmed, and Gmin were satisfactorily preserved; however, the TFL was clearly atrophic. In the ALS approach, where entry is made between Gmed and TFL, atrophy of the TFL due to superior gluteal nerve injury must be tolerated to some extent.

Union, Knee Alignment, and Clinical Outcomes of Patients Treated With Autologous Bone Grafting for Medial Tibial Defects in Primary Total Knee Arthroplasty.

Autologous bone grafting is an established method to overcome bone deficiencies in primary total knee arthroplasty (TKA). However, recently, metal augments have been used by many surgeons. Although autologous bone grafting is a common technique, few large studies have described its success in achieving bone union in primary TKA. The goal of this study was to evaluate primary TKA with autologous bone grafting for tibial defects. A total of 68 knees that had undergone arthroplasty with autologous bone grafting with more than 1 year of follow-up were evaluated. Average follow-up was 6.6 years (range, 1.2-14.6 years). The autologous bone grafting procedure attached the proximal portion of the tibial resection from the lateral side to the bone graft on the medial side with 2 screws. The prosthesis, which had a standard and nonrevision stem, was implanted with cement. Bone union was assessed with fluoroscopic radiography with a weight-bearing anteroposterior view. The rate of bone union was 97% (65 knees). Correction of preoperative alignment was achieved and maintained until final follow-up. Postoperative knee angle and knee and function scores showed significant improvement. One infection occurred, but there were no local complications, such as backout of screws or collapse of bone grafts. The authors believe that autologous bone graft within TKA is a relatively simple and effective procedure that provides good bone union. [Orthopedics. 2017; 40(4):e604-e608.].