Safety and clinical efficacy of double posterolateral coaxial portals for endoscopic management of posterior ankle impingement syndrome.

Background: This study aims to analyze the safety and clinical efficacy of using double posterolateral coaxial portals for endoscopic treatment of posterior ankle impingement syndrome (PAIS), a procedure that has gained popularity in recent times. Methods: Six fresh foot samples were randomly selected to measure the distances of two posterolateral portals to the sural nerve in different positions (plantar flexion 10°, dorsiflexion 30°, and plantar flexion 30°) for safety evaluation. A prospective analysis was conducted on the clinical efficacy of the operative approach for endoscopic management of posterior ankle impingement syndrome, including evaluation of effectiveness and complications. Results: In this study, the mean distances of the first and second portals to the sural nerve were measured in different ankle positions. The distances were found to be 2.26 ± 0.22 cm and 1.59 ± 0.12 cm in the plantar flexion 10° position, 2.21 ± 0.21 cm and 1.55 ± 0.12 cm in the dorsiflexion 30° position, and 2.46 ± 0.29 cm and 1.73 ± 0.19 cm in the plantar flexion 30° position, demonstrating a significant safety margin from the nerve. A total of 38 patients underwent endoscopic treatment for posterior ankle impingement syndrome using double posterolateral coaxial portals between January 2012 and December 2017. This surgical approach provided access to the subtalar joint and posterior ankle region. The patients were followed up for an average of 38.2 months (24-72 months), with a satisfaction rate of 94.7%. There were no reported complications, and significant improvements were observed in both visual analogue scale (VAS) and The American Orthopedic Foot and Ankle Society Score (AOFAS) scores postoperatively. The VAS score decreased from 5.68 to 0.51 (P < 0.001), while the AOFAS score increased from 71.68 to 92.34 (P < 0.001), resulting in an excellent/good rate of 97.3%. Conclusion: The use of double posterolateral coaxial portals in the treatment of posterior ankle impingement syndrome offers several advantages, including improved safety, reduced risk of nerve injury, enhanced visualization of the posterior ankle and subtalar joint, favorable clinical outcomes, and minimal complications.

Application of 3 dimension-printed injection-molded polyether ether ketone lunate prosthesis in the treatment of stage III Kienböck's disease: A case report.

BACKGROUND: Polyether ether ketone (PEEK) is a high-performance medical polymer, and there are some clinical cases of PEEK prosthesis implantation. However, application of 3D-printed injection-molded PEEK lunate prosthesis for treatment of stage III Kienböck's disease has not been reported. This study's purpose was to analyze the clinical efficacy of 3D-printed injection-molded PEEK lunate prosthesis in the treatment of stage III Kienböck's disease and thus provide a good therapeutic choice for Kienböck's disease. CASE SUMMARY: We report a patient with stage III Kienböck's disease. With the healthy lunate bone as reference, 3D lunate reconstruction was performed using a mirroring technique. A PEEK lunate prosthesis was prepared by 3D printing and injection molding, and then it was inserted into the original anatomical position after removing the necrotic lunate bone. Wrist pain and function, anatomical suitability of the lunate prosthesis, and complications were evaluated and analyzed postoperatively. At the last visit (one year after surgery), the range of motion, grasp force, visual analog scale score and Cooney score of the affected wrist were significantly improved, and postoperative X-ray examination indicated that the lunate prosthesis had good anatomical suitability for adjacent bony structures. CONCLUSION: The 3D-printed injection-molded PEEK lunate prosthesis demonstrated definite efficacy in treating stage III Kienböck's disease.

Analysis of the stress distribution of the subtalar joint and fusion efficacy after double-screw insertion.

BACKGROUND: Screw fixation is a typical technique for the isolated subtalar joint. However, no consensus has been reached on how to select the most suitable insertion position and direction. This study aims to find the ideal screw insertion and then explore its influence on the clinical efficacy of subtalar fusion by analyzing the effects of different cannulated screw insertions on the stress distribution, anti-rotary strength, and anti-inversion/eversion strength of the subtalar joint. METHODS: In this study, we investigated three cannulated screw insertions for subtalar fusion: screw insertion with the most uniform stress distribution (group A), lateral-medial parallel screw insertion (group B), and traditional longitudinally parallel screw insertion (group C). The effects of these three insertions on the loading stress of the subtalar joint (including stress distribution, anti-inversion/eversion strength, and anti-rotary strength) were comparatively analyzed with the three-dimensional finite element method to screen the ideal screw insertion. Moreover, a prospective study was conducted to analyze the influence of the ideal screw insertion on subtalar fusion, including the fusion rate, fusion time, and clinical efficacy (VAS score, AOFAS score, and complications). RESULTS: Group B was worse than group A with respect to the stress distribution uniformity, but slightly better than group C, and better than both groups A and C in terms of the anti-rotary strength and anti-inversion/eversion strength. The screw insertion based on the most uniform stress distribution is not feasible in surgery. Therefore, the lateral-medial antiparallel screw insertion is the ideal insertion. From January 2012 to June 2016, 48 cases were treated by subtalar fusion with the ideal screw insertion, and then followed up for 30.6 months (12-48 months). The fusion was proved in all 48 cases with a fusion rate of 100% by X-ray or CT scan. The mean time of fusion was 12.8 weeks (12-16 weeks). The VAS score decreased from 6.00 before operation to 1.03 on the last visit (P < 0.05), and the AOFAS score increased from 57.0 to 85.6 (P < 0.05), with a good and excellent rate of 95.8%. CONCLUSIONS: The lateral-medial parallel screw insertion not only demonstrates a good stress distribution profile of the subtalar joint but also has advantages such as easy localization and operation during surgery, as well as a high fusion rate and few complications after surgery. Therefore, it is a safe, accurate, and effective fixation mode that is worthy of being popularized clinically.

Initial stability and stress distribution of ankle arthroscopic arthrodesis with three kinds of 2-screw configuration fixation: a finite element analysis.

BACKGROUND: Arthroscopic ankle arthrodesis (AAA) is recognized as the standard treatment for the end-stage ankle arthritis. Two-screw configuration fixation is a typical technique for AAA; however, no consensus has been reached on how to select most suitable inserted position and direction. For better joint reduction, we developed a new configuration (2 home run-screw configuration: 2 screws are inserted from the lateral-posterior and medial-posterior malleolus into the talar neck) and investigated whether it turned out to be better than the other commonly used 2-screw configurations. METHODS: In this study, we investigated three kinds of 2-screw configurations: 2 "home run"-screw configuration (group A), crossed transverse configuration (the screw is inserted from the medial malleolus into the anterior talus and the other from the lateral tibia maintains posterior talus, group B), and 2 parallel screw configuration (2 parallel screws are inserted from the posteromedial side of the tibia into talus, group C). The effects of the above three insertions on the loading stress of the tibio-talar joint were comparatively analyzed with a three-dimensional finite element model. RESULTS: Group A was better than groups B and C in respect of stress distribution uniformity and superior to both groups B and C in anti-flexion strength and anti-internal rotation strength. Group A was slightly worse than group C but better than group B in anti-dorsiflexion and anti-valgus and varus strength. CONCLUSIONS: Two "home run"-screw configuration facilitates the reduction of anterior talus dislocation of end-stage ankle arthritis. Our finite element analysis demonstrates the configuration is superior to crossed transverse and parallel configuration for arthroscopic ankle arthrodesis in terms of stress distribution and initial stability.

Tibiotalocalcaneal arthrodesis with headless compression screws.

BACKGROUND: Tibiotalocalcaneal arthrodesis with headless compression screws has not been previously reported. We hypothesized that these screws could be suitable for tibiotalocalcaneal arthrodesis because of their special design. This study aimed to evaluate the clinical outcomes of patients undergoing tibiotalocalcaneal arthrodesis with headless compression screws for the treatment of severe arthropathy of the ankle and subtalar joint. METHODS: From 2010 to 2015, 23 patients with severe ankle and subtalar arthropathy underwent tibiotalocalcaneal arthrodesis. All surgeries were completed by a senior surgeon in the same hospital. These patients were 18~76 years (mean 54.6 years) old; the duration of their disease was 9~38 months (mean 13.2 months). The study population included 12 males and 11 females; 12 patients underwent surgery on the left and 11 on the right. Indications for surgery included avascular necrosis of the talus (n = 14), severe posttraumatic arthritis (n = 4), osteoarthritis (n = 2), terminal tuberculous arthritis (n = 1), rheumatoid arthritis (n = 1) and Charcot neuroarthropathy (n = 1). A lateral oblique incision was performed to expose the subtalar joint, and an anteromedial longitudinal incision was used to expose the ankle joint. After the articular surfaces were removed, the tibia, talus and calcaneus were carefully aligned and fixed with two headless compression screws. Patients were followed up at 6 weeks and 3, 6 and 9 months after surgery; they were evaluated by Roles and Maudsley patient satisfaction scores, the American Orthopaedic Foot & Ankle Society (AOFAS) Ankle-Hindfoot Score, visual analogue scale (VAS) score and radiographic evaluation. RESULTS: Seventeen patients were studied, with a mean follow-up time of 6.5 months (range 5-24). The mean Roles and Maudsley patient satisfaction score was 1.41 at the last follow-up; most of the patients were satisfied with the surgery results. The mean preoperative AOFAS Ankle-Hindfoot Score was 29.6 (range 18-37), while the mean last follow-up AOFAS Ankle-Hindfoot Score was 68.5 (range 61-80). The VAS score for preoperative functional pain was 6.95 (range 3-10) compared to 1.56 (range 0-3) postoperatively (P < 0.001). The mean surgical duration was 57 (range 42-125) min. The mean time to union was 3.8 months (range 3-12 months); fusion of the ankle and subtalar joint was successful in all patients. One patient experienced delayed wound healing. CONCLUSIONS: Tibiotalocalcaneal arthrodesis with headless compression screws for the treatment of severe arthropathy of the ankle and subtalar joint is an effective treatment that is minimally invasive and is associated with a short operation time, high fusion rate, low incidence of complications and good postoperative recovery.

Effects on Subtalar Joint Stress Distribution After Cannulated Screw Insertion at Different Positions and Directions.

We investigated the effects on subtalar joint stress distribution after cannulated screw insertion at different positions and directions. After establishing a 3-dimensional geometric model of a normal subtalar joint, we analyzed the most ideal cannulated screw insertion position and approach for subtalar joint stress distribution and compared the differences in loading stress, antirotary strength, and anti-inversion/eversion strength among lateral-medial antiparallel screw insertion, traditional screw insertion, and ideal cannulated screw insertion. The screw insertion approach allowing the most uniform subtalar joint loading stress distribution was lateral screw insertion near the border of the talar neck plus medial screw insertion close to the ankle joint. For stress distribution uniformity, antirotary strength, and anti-inversion/eversion strength, lateral-medial antiparallel screw insertion was superior to traditional double-screw insertion. Compared with ideal cannulated screw insertion, slightly poorer stress distribution uniformity and better antirotary strength and anti-inversion/eversion strength were observed for lateral-medial antiparallel screw insertion. Traditional single-screw insertion was better than double-screw insertion for stress distribution uniformity but worse for anti-rotary strength and anti-inversion/eversion strength. Lateral-medial antiparallel screw insertion was slightly worse for stress distribution uniformity than was ideal cannulated screw insertion but superior to traditional screw insertion. It was better than both ideal cannulated screw insertion and traditional screw insertion for anti-rotary strength and anti-inversion/eversion strength. Lateral-medial antiparallel screw insertion is an approach with simple localization, convenient operation, and good safety.

Differential efficacy of subtalar fusion with three operative approaches.

BACKGROUND: There are many existing operative approaches for subtalar fusion; however, no optional strategy of operative approach has been developed yet. This study aimed to analyze the differential clinical efficacy of subtalar fusion with three operative approaches. METHODS: The clinical data of 102 patients from April 2008 to April 2012 were analyzed prospectively. These patients were divided into three groups with the random number table: group A, group B, and group C. The following parameters were compared among three groups: effective exposure area and exposure time of subtalar joint, intraoperative bleeding volume, postoperative complications, fusion time, fusion rate, AOFAS score and VAS score before and after operation. RESULTS: In the exposure area score, there was no statistically significant difference between group A and group C (P > 0.05) ,but with a statistically significant difference between group A/C and group B (P < 0.05). In exposure time and intraoperative bleeding volume, there was no statistically significant difference between group A and group B (P > 0.05) but with a statistically significant difference between group A/B and group C (P < 0.05). In three groups, there was a statistically significant difference in both AOFAS score and VAS score before operation and at 6 months/12 months/last visit after operation (P < 0.05). The incidence of complications in the three groups was 8.8%, 12.5% and 19.4%. No statistically significant differences in fusion rate and fusion time were observed among the three groups (P > 0.05). CONCLUSION: Three operative approaches have different indications, All the three operative approaches do not influence the fusion rate and fusion time of subtalar joint. The lateral tarsal sinus approach is inferior to the posterior-lateral L approach and the approach from the inferior tip of fibula to the basilar part of the fourth metatarsal bone in the exposure area, while the lateral tarsal sinus approach and the approach from the inferior tip of fibula to the basilar part of the fourth metatarsal bone are superior to the posterior-lateral L approach in the exposure time, intraoperative bleeding volume, and incidence of complications.

[Clinical efficacy of subtalar joint arthrodesis with percutaneous opposite parallel cannulated screws].

OBJECTIVE: To explore the clinical efficacy of subtalar joint arthrodesis with percutaneous opposite parallel cannulated screws for severe subtalar joint arthritis. METHODS: A total of 88 patients with 90 feet underwent subtalar joint fusion under four different incisions from April 2008 to April 2012. There were 56 males and 32 females with a mean age of 43.7 (15-74) years. All of them were evaluated by radiography or computed tomography (CT) scan and assessed by the rating scores of visual analog scale (VAS) and American Orthopedic Foot and Ankle Society (AOFAS). RESULTS: Among them, 68 cases were followed up for an average of 18.5 (6-48) months. Fusion was confirmed on radiography or CT in 67 cases with a fusion rate of 98.5%. The mean duration of fusion was 13.8 (6-28) weeks, the mean VAS score decreased from 6.00 to 1.03 points (P < 0.05) and the mean AOFAS score improved from 57.0 to 80.6 points (P < 0.05) with a good-and-excellent rate of 80.8%. CONCLUSION: Subtalar joint arthrodesis with percutaneous opposite parallel cannulated screws is recommend for severe subtalar joint arthritis. Such a procedure has a high fusion rate, excellent clinical outcomes and fewer complications.