Predictors of Vertebral Endplate Fractures after Oblique Lumbar Interbody Fusion.

Background: Cage subsidence after oblique lumbar interbody fusion (OLIF) induces restenosis and adversely affects patient outcomes. Many studies have investigated the causes of subsidence, one of which is endplate fracture (EF). This study aimed to identify predictors of EF after OLIF. Methods: This retrospective study reviewed consecutive patients who underwent OLIF at a single institute between August 2019 and February 2022. A total of 104 patients were enrolled. The patients' demographic data and surgical details were collected through chart reviews. Radiographic variables were measured. Related variables were also analyzed using binomial logistic regression, dividing each group into those with versus without EF. Results: EF occurred at 30 of 164 levels (18.3%), and the binary logistic analysis revealed that sex (odds ratio [OR], 11.07), inferior endplate concave depth (OR, 1.95), disc wedge angle (OR, 1.22), lumbar lordosis (OR, 1.09), pelvic incidence (OR, 1.07), sagittal vertical axis (OR, 1.02), sacral slope (OR, 0.9), L3-4 level (OR, 0.005), and L4-5 level (OR, 0.004) were significantly related to EF. Conclusions: OLIF in older Asian patients should be performed carefully after recognizing the high possibility of EF and confirming the factors that should be considered preoperatively.

Racial differences in prevalence and anatomical distribution of tarsal coalition.

Previous studies have reported a prevalence of tarsal coalition of 0.03-13%. Calcaneonavicular coalition is known as main anatomical type, and the bilateral occurrence of tarsal coalition is known to be 50% or more. These are the results of studies on Caucasians, there have been few studies targeting large number of East Asians so far. We hypothesized that the prevalence and characteristics of tarsal coalition in East Asians might differ from those in Caucasians. The medical records of 839 patients who underwent bilateral computed tomography on foot and ankle in our hospital from January 2012 to April 2021 were retrospectively reviewed. The overall prevalence was 6.0%, talocalcaneal coalition was the most common anatomical type. The overall bilateral occurrence was 56.5%, talocalcaneal coalition had the highest bilateral occurrence (76.0%) among anatomical types. Isolated union of the posterior facet was the most common subtype of talocalcaneal coalition (43.2%). Talocalcaneal coalition had a significantly higher proportion of coalition-related symptomatic patients than calcaneonavicular coalition (p = 0.019). Our study showed a similar trend to other East Asian studies, confirming the existence of racial differences. The possibility of tarsal coalition in foot and ankle patients in East Asians should always be considered, and bilateral examination is essential for diagnosis.

Characteristics of Synovial Fistula of the Ankle Joint: A Case Series.

(1) Background: Little is known about the etiology, clinical features, diagnosis methods, treatments, and the prognosis of synovial fistula of the ankle joint. The purpose of this study is to investigate the clinical features of synovial fistula of the ankle joint. (2) Methods: Between March 2003 and December 2018, 40 cysts associated with synovial fistula of the ankle joint were treated consecutively by two surgeons. Case histories, clinical manifestations, intraoperative findings, surgical treatment methods, and treatment outcomes were evaluated to characterize fistula-associated cysts. The clinical results were assessed using the visual analog scale (VAS) and the American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot functional scores, preoperatively and at the last follow-up. (3) Results: The main complaints were ankle instability and pain (15 patients), pain only (15 patients), instability (seven patients), and cosmetic problems (three patients). Eleven patients had a cyst with an open skin wound, and eight of these patients had undergone surgery under a misdiagnosis of bursitis. Cysts were located anterior to the lateral malleolus in 22 cases, next to the lateral malleolus in 13 cases, posterior to the lateral malleolus in three cases, and across the entire lateral malleolus in two cases. Mean VAS and AOFAS scores improved from 5.2 (range, from 1 to 7) and 72.3 (range, from 65 to 87) preoperatively to 1.1 (range, from 0 to 3) and 93.6 (range, from 85 to 100), respectively, at final follow-up visits. (4) Conclusions: Cyst occurrence due to a synovial fistula should be considered when treating a cyst around the lateral malleolus. Fistula repair and reinforcement with fibular periosteum provides a good treatment option for cysts attributed to synovial fistula of the ankle that fail to respond to conservative treatment.

Combined Transfibular and Anterior Approaches Increase Union Rate and Decrease Non-Weight-Bearing Periods in Ankle Arthrodesis: Combined Approaches in Ankle Arthrodesis.

The transfibular approach is a widely used method in ankle arthrodesis. However, it is difficult to correct coronal plane deformity. Moreover, it carries a risk of nonunion and requires long periods of non-weight-bearing because of its relatively weak stability. We hypothesized that the transfibular approach combined with the anterior approach in ankle arthrodesis wound yield a higher fusion rate and shorter non-weight-bearing period. This study was performed to evaluate the clinical and radiographic results and postoperative complications in ankle arthrodesis using combined transfibular and anterior approaches in end-stage ankle arthritis. Thirty-five patients (36 ankles) with end-stage ankle arthritis were consecutively treated using ankle arthrodesis by combined transfibular and anterior approaches. The subjects were 15 men and 20 women, with a mean age of 66.5 years (46-87). Clinical results were assessed using the visual analog scale (VAS) for pain, the American Orthopaedic Foot and Ankle Society (AOFAS) scores, and the ankle osteoarthritis scale (AOS) preoperatively and at the last follow-up. Radiographic results were assessed with various radiographic parameters on ankle weight-bearing radiographs and hindfoot alignment radiographs. All clinical scores significantly improved after surgery. Union was obtained in all cases without additional surgery. Talus center migration (p = 0.001), sagittal talar migration (p < 0.001), and hindfoot alignment angle (p = 0.001) significantly improved after surgery. One partial skin necrosis, two screw penetrations of the talonavicular joint, and four anterior impingements because of the bulky anterior plate occurred after surgery. In conclusion, combined transfibular and anterior approaches could be a good method to increase the union rate and decrease the non-weight-bearing periods in ankle arthrodesis.