Early outcomes of the oxford unicompartmental knee arthroplasty: 140 cases from a single institute in Taiwan.

BACKGROUND: The clinical and radiologic outcomes of the Oxford Unicompartmental Knee Arthroplasty utilizing Microplasty® instrumentation have not been extensively investigated in Taiwanese patients. Despite the efficacy of this treatment for unicompartmental knee diseases, its specific impact on this population remains unknown. METHODS: We retrospectively analyzed prospectively collected data of patients who underwent OUKA with MP between 2018 and 2021, including demographic information, component position, pre- and postoperative knee range of motion (ROM), numeric rating scale (NRS), and 2011 Knee Society Score-functional activity score (2011 KSS-FAS). We compared pre- and postoperative data and analyzed the correlation between clinical and radiographic outcomes. RESULTS: Among 140 patients with an average age of 66.8 years, predominantly female, the majority exhibited components that fell within the radiographically acceptable tolerance ranges. The mean 2.5-year follow-up revealed significant improvements in knee ROM from 102.6° ± 12.9° to 127.3° ± 9.8° (p < 0.05), pain reduction from 7.7 ± 0.8 to 0.4 ± 0.7 (p < 0.001), and KSS-FAS from 30.7 ± 10.5 to 94.3 ± 5.2 (p < 0.001). Notably, a tibial component medial overhang within tolerance predicted shorter hospital stays, and a higher preoperative KSS correlated with lower postoperative NRS. No independent variables were identified as predictors of a higher postoperative KSS. CONCLUSION: Our study on OUKA with MP in Taiwanese patients reveals promising early clinical and radiographic outcomes. Tibial component medial overhang <3 mm is associated with shorter hospital stays, and a higher preoperative KSS predicts lower NRS at 1 year postoperatively.

Exploring Physical Lumbar Microvascular Geometry Through Endoscopy and Illustrations: Implications for Clinical Interpretation.

STUDY DESIGN: Retrospective Study. OBJECTIVES: Minimally invasive endoscopic spinal surgery is gaining popularity, but our understanding of the lumbar spine's microvascular geometry relies heavily on cadaver studies and textbook illustrations. Additionally, inconsistent nomenclature of vessels in the literature hampers effective communication among surgeons. This study aims to improve the clarity and comprehensibility of the lumbar spinal microvascular geometry under endoscopic view. METHODS: The study included 400 patients who underwent endoscopic spinal surgery for lumbar spinal canal stenosis and foraminal stenosis. The surgeries were performed by an experienced surgeon using either the interlaminar or transforaminal approach. Endoscopic video recordings were further analyzed to map the microvascular geometry and common bleeding foci. The observed results were cross-referenced with existing literature to reconstruct a comprehensive view of the vascular anatomy. RESULTS: The transforaminal approach commonly encounters bleeding foci originating from the major branches of the segmental lumbar artery and the emissary veins within the foramen. The interlaminar approach primarily encounters bleeding foci from the muscle vessels in the dorsal lamina, which are believed to be located near the ends of the three main branches. In the intracanal region, epidural vessels form a rotary loop above the disc, which can contribute to most of the bleeding during discectomy. CONCLUSIONS: This study provides a comprehensive understanding of the microvascular anatomy in the lumbar spine during endoscopic spinal surgery. Recognizing the geometry will help surgeons anticipate and control bleeding, reducing the risk of complications. The findings contribute to the improvement of surgical techniques and patient safety in endoscopic spinal surgery.

Enhancing endoscopic foraminal decompression in adult isthmic spondylolisthesis: the potential influence of lateral recess isthmic spur and our case series of an innovative craniocaudal interlaminar approach via unilateral biportal endoscopic spinal surgery.

BACKGROUND: The NASS guideline cannot recommend any of the surgical treatment options toward adult isthmic spondylolisthesis (AIS) since 2014. After the introduction of endoscopic decompression, instead of treating the spondylolysis itself, treatment can specifically target the refractory radicular pain developed during the degeneration progress without devastating the peripheral soft tissue. However, we noticed that endoscopic transforaminal decompression seems to be less effective in AIS compared to other types of degenerative spondylolisthesis. Thus, we came up with a novel craniocaudal interlaminar approach, utilizing the proximal adjacent interlaminar space to perform bilateral decompression and observed the pathoanatomy of pars defect directly and tried to identify the cause of decompression failure. METHODS: From January 2022 to June 2022, 13 patients with AIS underwent endoscopic decompression via the endoscopic craniocaudal interlaminar approach and were followed up for at least 6 months. Visual Analogue Scale, Oswestry Disability Index and MacNab scores were recorded to monitor patients' clinical recovery. All endoscopic procedures were recorded and reviewed to illustrate the pathoanatomy. RESULTS: Four patients required minor revision via the same technique. One of them required it due to incomplete isthmic spur resection, two due to neglected disc protrusion, and the other due to root subpedicular kinking in higher grade anterolisthesis. All patients' clinical condition improved significantly subsequently. After reviewing the endoscopic video, we have observed that the hook-like, ragged spur originating from the isthmic defect extends beyond the region around the foramen. Instead, it extends proximally into the adjacent lateral recess, resulting in impingement along the fracture edge above the index foramen and, in some cases, even in the extraforaminal area. CONCLUSIONS: The broad spanning isthmic spur extending to the proximal adjacent lateral recess might be the reason why the transforaminal approach yielded less satisfactory results due to the incomplete decompression result from approach related restriction. Our study demonstrated an optimistic outcome by applying decompression from the upper level. Therefore, we propose that the craniocaudal interlaminar approach might be a better route for decompression in adult isthmic spondylolisthesis.

Treatment of acute distal radioulnar joint instability with distal oblique bundle augmentation of the interosseous membrane by suture-button suspension: A case series.

The stability of distal radioulnar joints is afforded by bony radioulnar articulation and peripheral soft-tissue stabilizers. The primary soft-tissue stabilizers are structures that surround the distal radioulnar joint and are collectively referred to as the triangular fibrocartilaginous complex. Among the stabilizers, the volar and dorsal radioulnar ligaments contribute the most to the stability of distal radioulnar joints. For acute traumatic distal radioulnar joint instability accompanied by purely ligamentous injury, traditional surgical treatments involve the repair or reconstruction of the distal radioulnar ligament; however, these intra-articular procedures are highly invasive and difficult. The extra-articular reconstruction of the secondary stabilizer such as the distal oblique bundle of the interosseous membrane has attracted significant attention in recent years; however, most studies have only conducted cadaveric or laboratory modelbased investigations. In this article, we present three patients who suffered from acute dorsal wrist pain after a trauma event. Radiographic and physical examinations revealed distal radioulnar joint instability. All patients were treated with minimally invasive suture-button suspension augmentation in the direction of distal oblique bundle of the interosseous membrane. The instability was resolved after the surgical procedure, but two patients developed ulnar wrist pain and one patient underwent implant removal. All patients have been continually followed at our outpatient department and exhibited stable wrists, despite mild limitation in the range of motion after the procedure. In conclusion, acute traumatic distal radioulnar joint instability may be sufficiently treated with suture-button suspension for augmentation of the distal oblique bundle; however, some obstacles impede the in vivo adoption of this treatment.

A novel approach to distal femur: a minimally invasive technique for supracondylar and intercondylar fracture.

BACKGROUND: For treating distal femur fractures, minimally invasive plating techniques with indirect reduction of the metadiaphysis while minimizing the damage to the peripheral soft tissue has gradually become the standard. However, all the current approaches use a straight or lazy curved incision adjacent to the patella or along the lateral side of the femur, which allows for easier proximal extension but increases the incision length. METHODS: In order to achieve a more physiological and esthetic outcome while leaving the metadiaphysis untouched, we developed an approach using a lambda-shaped incision, which sacrifices the potential for proximal extension but preserves much more peripheral soft tissue. Here, we describe our technique and our experience with it in 19 patients (12 men and 7 women). RESULTS: Fractures healing by first intention was observed in all patients. The postoperative knee range of motion can reach up to 90° in most of the patient. Clinically, 9 patients had excellent results, 6 had good results, 3 had fair results, and 2 had loss of follow-up. CONCLUSIONS: Our minimally invasive lambda-incision approach allows sufficient visual access to almost the entire joint surface, including the entire lateral femoral condyle, trochlear surface, and distal medial condyle, where reduction is required. The lambda incision provides a much larger window than that offered by a same-length straight incision. The vertical turn at the mid-patellar level parallels the skin crease and geniculate artery, reducing soft tissue damage and resulting in a smooth healing wound. Moreover, plate and distal screw insertion is easier than that through a straight incision. Because the metadiaphysis region is mostly left untouched, ideal fracture-healing environment is preserved.

A Novel Arthroscopic Transosseous Procedure for Rotator Cuff Repair: An Economical Freehand Method.

Open transosseous repair was historically considered the gold-standard surgical solution for rotator cuff tears; however, with advancements in arthroscopic surgery, this procedure was largely replaced by anchor-based techniques. Yet, the ability of anchor-based techniques to achieve similar biomechanical fixation remains uncertain.In this article, we describe a reproducible, economical, arthroscopic anchorless transosseous rotator cuff repair technique that uses an Omega configuration. This technique involves two bone tunnels and four high-strength polyethylene sutures and is suitable for medium-to-large rotator cuff tears that would alternatively need multiple anchors. This procedure not only maximizes the tendon-footprint contact area without using any implanted device but also theoretically lowers the bone laceration rate and is cost effective. In the current Technical Note, the procedure is described in detail along with several tips and tricks. CLASSIFICATIONS: Level I, shoulder; Level II, rotator cuff.

Treatment of Fabella syndrome with arthroscopic fabellectomy: a case series and literature review.

BACKGROUND: The fabella is a sesamoid bone in the posterolateral capsule of the human knee joint. In quadrupedal mammals, the fabella is believed to have a role similar to the patella in redirecting extension forces of the knee joint from one point to another. In bipeds, the fabella is not touching the back of the bent knee, and therefore the role in redirecting forces declines. Posterolateral knee pain can be associated with the irritation between the fabella and lateral femoral condyle, a phenomenon also known as fabella syndrome. In cases that are unresponsive to conservative management, surgical fabellectomy can be a successful treatment option. Among the surgical approaches, open resection is most commonly seen. There are also literature reporting arthroscopic-assisted open resection, but seldom mentioned the all-arthroscopic fabellectomy. CASE PRESENTATION: We present 3 patients with a long history (> 12 month) of posterolateral knee pain under suspicion of different pain origins. The diagnosis of fabella impingement was eventually made by ruling out of other causes. All the patients underwent all-arthroscopic fabellectomy for diagnosis and treatment. Investigations of the resected fabella suggested chronic impingement with apparent osteophyte formation and cartilage wearing of the articular side. All patients have been continually followed up at our outpatient department and reported to be pain free after the procedure. CONCLUSIONS: In the patients presenting posterolateral pain, fabella syndrome cannot be ignored due to its relative higher presence in Asian population. In our experience, the all-arthroscopic fabellectomy offers a smaller wound size, less post-operative pain, fewer days of hospitalization and quicker time to rehabilitation for the patients with chronic posterolateral knee pain caused by fabella syndrome.

Visualizing Ferroelectric Uniformity of Hf1-xZrxO2 Films Using X-ray Mapping.

Hf1-xZrxO2 (HZO) is a complementary metal-oxide-semiconductor (CMOS)-compatible ferroelectric (FE) material with considerable potential for negative capacitance field-effect transistors, ferroelectric memory, and capacitors. At present, however, the deployment of HZO in CMOS integrated circuit (IC) technologies has stalled due to issues related to FE uniformity. Spatially mapping the FE distribution is one approach to facilitating the optimization of HZO thin films. This paper presents a novel technique based on synchrotron X-ray nanobeam absorption spectroscopy capable of mapping the three main phases of HZO (i.e., orthorhombic (O), tetragonal (T), and monoclinic (M)). The practical value of the proposed methodology when implemented in conjunction with kinetic-nucleation modeling is demonstrated by our development of a T → O annealing (TOA) process to optimize HZO films. This process produces an HZO film with the largest polarization values (Ps = 64.5 µC cm-2; Pr = 35.17 µC cm-2) so far, which can be attributed to M-phase suppression followed by low-temperature annealing for the induction of a T → O phase transition.