Does the Sagittal Radiographic Morphology of Subtalar Joint Affect the Alignment of Foot?

OBJECTIVES: The etiology of flatfoot and cavus foot is multicausal and controversial. So far, no literature reports the relationship between the sagittal morphology of subtalar joint and the alignment of foot. The purpose of this study was to explore whether the subtalar alignment would influence the configuration of foot. METHODS: From January 2017 to January 2020, we included 109 feet in the flatfoot group, 95 feet in the cavus group, and 104 feet in the control group in this retrospective comparative study. The Gissane angle and calcaneal posterior articular surface inclination angle represented the sagittal morphology of the subtalar joint. Meary's angle, calcaneal pitch angle, and talar pitch angle reflected the alignment of foot. They were measured in the weightbearing foot X-rays. The angles in different groups were compared via Mann-Whitney U test. We calculated the correlation between the sagittal alignment of subtalar joint and the alignment of foot using Spearman's correlation analysis. Interobserver and intraobserver reliability were calculated. RESULTS: The Gissane angle, calcaneal posterior articular surface inclination angle, Meary's angle, talar pitch angle, and calcaneal pitch angle were significantly different in the three groups. The Gissane angle had an excellent correlation with the Meary's angle (r = 0.850, p < 0.0001), and the talar pitch angle (r = -0.825, p < 0.0001), and a good correlation with the calcaneal pitch angle (r = 0.638, p < 0.0001). The calcaneal posterior articular surface inclination angle had an excellent correlation with the Meary's angle (r = -0.902, p < 0.001), and the talar pitch angle (r = 0.887, p < 0.0001), and a good correlation with the calcaneal pitch angle (r = -0.702, p < 0.0001). The interobserver and intraobserver reliability for all radiographic measurements was good to excellent. CONCLUSION: A subtalar joint with a larger Gissane angle and a more horizontal calcaneal posterior articular surface angle tended to have a higher foot arch and vice versa. The inspiration from this study was that the deformities of flatfoot and cavus foot may relate to the subtalar deformity.

Dynamic Response of CFRP Reinforced Steel Beams Subjected to Impact Action Based on FBG Sensing Technology.

The in-situ health condition of carbon fiber reinforced polymer (CFRP) reinforced structures has become an important topic, which can reflect the structural performance of the retrofitted structures and judge the design theory. An optical fiber-based structural health monitoring technique is thus suggested. To check the effectiveness of the proposed method, experimental testing on smart CFRP reinforced steel beams under impact action has been performed, and the dynamic response of the structure has been measured by the packaged FBG sensors attached to the surface of the beam and the FBG sensors inserted in the CFRP plates. Time and frequency domain analysis has been conducted to check the structural feature of the structures and the performance of the installed sensors. Results indicate that the packaged Fiber Bragg Grating (FBG) sensors show better sensing performance than the bare FBG sensors in perceiving the impact response of the beam. The sensors embedded in the CFRP plate show good measurement accuracy in sensing the external excitation and can replace the surface-attached FBG sensors. The dynamic performance of the reinforced structures subjected to the impact action can be straightforwardly read from the signals of FBG sensors. The larger impact energies bring about stronger impact signals.

Revision lateral ankle ligament reconstruction for patients with a failed modified Brostrom procedure.

PURPOSE: The Brostrom-Gould procedure has been considered as a gold standard operative technique for chronic lateral ankle instability. Despite the popularity and excellent outcomes of the modified Brostrom procedure, some patients still experience recurrence of ankle instability. Few studies reported outcomes of revision reconstruction for patients with a failed modified Brostrom procedure. This study aimed to evaluate the outcomes of a percutaneous anatomic revision lateral ankle ligament reconstruction for patients with a failed modified Brostrom procedure. METHODS: From March 2017 to April 2020, 21 patients with persistent ankle instability after a modified Brostrom procedure underwent revision lateral ankle ligament reconstruction. The operation was performed through minimally invasive incisions. Functional assessment was performed using the Karlsson-Peterson ankle scoring system (KP) and the Visual Analogue Scale (VAS). The questionnaires of KP and VAS were completed before surgery and at the last follow-up. Patients' subjective satisfaction level was graded as excellent, good, fair, and poor. Preoperative and postoperative anterior talar displacement and varus talus tilt angle in stress radiographs were recorded. RESULTS: The average age at the revision surgery time was 39.6years. The mean follow-up was 39.2months. The VAS score improved from 4.1 ± 1.5 preoperatively to 1.3 ± 1.3 at the final follow-up (p < .05). The KP score improved from 59.0 ± 20.2 preoperatively to 88.2 ± 9.6 at the last follow-up (p < .05). The mean varus talar tilt angle was 14.1 ± 3.9 mm preoperatively versus 4.9 ± 4.7 mm at the final follow-up (p < .05). The mean anterior talar displacement was 12.8 ± 2.2 mm versus 5.6 ± 3.7 mm at the last follow-up (p < .05). CONCLUSIONS: The revision anatomic reconstruction of the lateral ligaments of the ankle is effective for patients with recurrent instability after a failed modified Broström procedure.

Radiographic and clinical outcomes of minimally invasive surgery versus open osteotomies for the correction of hallux valgus.

PURPOSE: Hallux valgus is a common disease which causes pain and dysfunction of the foot. Although numerous methods of procedures have been introduced, a single procedure cannot correct all deformities of hallux valgus. The study aims to evaluate the radiographic and clinical effectiveness of a new minimally invasive surgery (MIS) versus open Chevron-Akin procedures. METHODS: This was a retrospective comparative study. Data were collected from May 2018 to January 2020. A total of 27 patients (31 feet) undergoing MIS for hallux valgus were included in this study. The average age of patients underwent MIS was 59.9 years. The mean follow-up was 25.1 months. Open osteotomies were performed in 30 patients (31 feet) during the same period. The mean age of these patients at the time of surgery was 59.1 years. The mean follow-up was 26.1 months. Pre-operative and post-operative radiographic outcome measures included HVA, IMA, DMAA, the Sgarlato's angle and the length of the first metatarsal, and distance between the dorsal cortex of first and second metatarsal necks. The AOFAS and VAS were used to assess foot function. RESULTS: The preoperative HVA in MIS group and open group were 34.8° and 33.1° respectively. The post-operative HVA were 20.4° and 13.7°. The pre-operative IMA in MIS group and open group were 13.0° and 12.1°. The post-operative IMA were 11.4° and 5.5° respectively. The pre-operative DMAA were 14.8° and 15.1° respectively. The post-operative DMAA were 6.3° and 8.7°. The AOFAS increased from 44.0 to 90.2 in MIS group and from 47.6 to 89.5 in open group. The VAS decreased from 7.3 to 1.3 in MIS group and from 7.1 to 1.2 in open group. CONCLUSION: Although open osteotomies were superior than MIS in HVA and IMA, MIS showed advantages in correcting DMAA. MIS provided equivalent functional outcomes compared to open surgery.

Hallux Valgus Correction Comparing Percutaneous Oblique Osteotomy and Open Chevron Osteotomy at a 2-year Follow-up.

OBJECTIVE: This study aimed to compare the percutaneous oblique osteotomy (POO) and the open chevron osteotomy technique for correction of hallux valgus deformity at a 2-year follow-up. METHODS: This is a retrospective study of consecutive patients undergoing operative correction of hallux valgus using one of two techniques (POO vs open chevron osteotomy) from 2014 to 2018. Forty eight feet (41 patients) that underwent the POO was compared with 64 feet (58 patients) that underwent open chevron osteotomy. The hallux valgus angle (HVA), intermetatarsal angle (IMA) and American Orthopedic Foot & Ankle Society Hallux Metatarsophalangeal-Interphalangeal scores (AOFAS-HMI) were assessed preoperatively and postoperatively at the 1, 2-year follow-up. The Manchester-Oxford Foot Questionnaire (MOXFQ) were assessed preoperatively and postoperatively at the 2-year follow-up. The VAS score was collected preoperatively and on 2 weeks,1 year and 2-year follow-up. RESULTS: Both groups achieved significant correction of the hallux deformity. The HVA in the POO group during the follow-up period were 12.5 ± 2.22 and 17.9 ± 9.31, respectively, and in the open chevron group were 14.1 ± 6.78 and 14.8 ± 7.83, respectively. The IMA in the POO group during the follow-up period were 7.61 ± 1.63 and 6.94 ± 1.53, respectively, and in the open chevron group were 6.89 ± 3.06 and 6.97 ± 2.95, respectively. Postoperative MOXFQ scores in all domains were significantly improved in both groups, however there was no significant difference in the improvement of any domain between POO and open groups at a 2-year follow-up. The AOFAS HMI scores in the POO group during the follow-up period were 86.5 ± 10.7 and 85.2 ± 13.8, respectively, and in the open chevron group were 88.2 ± 10.8 and 79.5 ± 23.7, respectively. The VAS scores in the POO group during the follow-up period were 2.00 ± 0.98, 2.00 ± 0.99 and 1.55 ± 1.11, respectively, and in the open chevron group were 5.51 ± 1.45, 2.56 ± 2.88 and 2.56 ± 2.88 respectively. The 1-year and 2-year follow-up outcomes between POO and open groups showed no significant difference regarding AOFAS HMI scores and VAS scores, however the POO group showed statistically significant improvement of VAS scores in the postoperative 2 weeks (P < 0.001). There was no statistical significance between the POO and open group in terms of complications rates (8.3% vs 12.5%, P = 0.480). CONCLUSION: The POO technique is reliable and shows a comparable outcome to the open chevron osteotomy. However, the POO technique shows significantly less pain in the first 2 weeks after surgery.

Osteotomy combined with lateral ligament reconstruction in treating osteochondral lesion in patients with talar injury and varus ankle.

ABSTRACT: This study aimed to investigate the therapeutic effects of osteotomy combined with lateral ligament reconstruction on the osteochondral lesion of patients with talar injuries and varus ankles.Seventy five patients with talar injuries and varus ankles who received osteotomy combined with lateral ligament reconstruction for the osteochondral lesions from June 2008 to December 2014 were retrospectively reviewed. Patients were followed up for 32.4 ±â€Š15.3 months after surgeries, and the AOFAS-AH score, VAS score and SF36 score were determined preoperatively and postoperatively. The iconographic data were compared preoperatively and postoperatively, including tibial anterior surface angle (TAS), TTS, TT, and tibial lateral surface angle (TLS) angles.After surgeries, the AOFAS-AF score increased from 43.2 ±â€Š8.1 to 82.1 ±â€Š5.6, the VAS score decreased from 6.9 ±â€Š2.3 to 1.8 ±â€Š1.5, and the SF36 score increased from 48.7 ±â€Š9.4 to 83.5 ±â€Š6.2. TAS increased from 83.3 ±â€Š5.1 to 90.3 ±â€Š6.1, TTS increased from 70.3 ±â€Š6.1 to 82.5 ±â€Š5.4, TT decreased from 12.9 ±â€Š6.1 to 6.9 ±â€Š5.7, and TLS increased from 76.5 ±â€Š4.1 to 81.2 ±â€Š3.3 (P < .05).Osteotomy combined with lateral ligament reconstruction is effective for the treatment of talar osteochondral lesion with varus ankle, which could relieve the arthritic symptoms induced by cartilage lesions. By correcting the force line on lower limbs and metapedes with osteotomy completely, the treatments on talar osteochondral lesion and lateral ligament reconstruction are the critical factors with better results.

Intra-articular opening osteotomy combined with lateral ligament reconstruction for varus ankle arthritis.

BACKGROUND: Takakura 3B ankle arthritis is featured as obliteration of ankle space with subchondral bone contact. Among these patients, some have medial distal tibial platform erosion. It is hard to treat this kind of patients. The purpose of this study was to evaluate the therapeutic outcomes of intra-articular opening osteotomy combined with lateral ligament reconstruction for Takakura 3B ankle arthritis with medial distal tibial platform erosion. METHODS: From September 2009 to May 2016, 17 patients with Takakura 3B ankle arthritis were reviewed, including 3 male and 14 female patients. All underwent the operation of intra-articular opening osteotomy combined with lateral ligament reconstruction. All patients were available for analysis. The main outcome measurements included TT angle, AOFAS score, VAS score, SF-36 scale, and AOS scale. RESULTS: All patients were followed for a mean follow-up of 87.2 months (range, 49 to 129 months). The VAS scale improved from 5.5 ± 1.6 to 2.3 ± 1.9. The mean AOFAS score improved from 47.7 ± 15.7 to 75.8 ± 12.0. The SF-36 scale improved from 41.6 ± 14.0 to 67.7 ± 14.6. The AOS improved from 60.9 ± 13.9 to 28.2 ± 17.7. The TT angle improved from 14.3 ± 5.0° to 5.3 ± 4.0°. The TAS and TLS changed from 83.4 ± 2.6° and 77.5 ± 2.3° to 90.7 ± 2.3° and 78.6 ± 2.2°. However, the LTAS was not corrected significantly. CONCLUSION: Intra-articular opening osteotomy combined with lateral ligament reconstruction is an effective method to treat varus ankle arthritis with medial distal tibial platform erosion.

[Treatment of severely osteoporotic vertebral compression fractures with the vertebral body stent system and percutanous kyphoplasty combined with zoledronic acid].

OBJECTIVE: To investigate the clinical efficacy of vertebral body stent (VBS) system and percutanous kyphoplasty (PKP) combined with zoledronic acid for the treatment of severely osteoporotic compression vertebral fractures (OVCFs). METHODS: The clinical data of 48 patients with osteoporotic thoracolumbar fractures treated from December 2017 to December 2018 were retrospectively analyzed, including 13 males and 35 females, aged 55 to 92 years old with an average (71.2±10.5) years. All patients were treated with VBS system PKP surgery, and zoledronic acid injection was used for anti-osteoporosis treatment after operation. The VAS scores ODI, the height of diseasedvertebral lost were compared before operation, 3 d and half a year after operation, and whether there was re-fracture of diseased or adjacent vertevrae after operation was observed. RESULTS: Before operation, 3 d and half a year after operation, VAS scores were 7.60±0.12, 3.00±0.46, 1.20±0.23, ODI were(82.00±0.32)%, (30.00±1.50) %, (18.00±0.16) %, the height of diseased vertebral lost were (12.00±0.43) mm, (3.00± 0.15) mm, (3.60±0.51) mm respectively. Postoperative VAS score, ODI, the height of diseased vertebral lost were obviously improved (P<0.05), and there was no significant difference between 3 d and half a year after operation (P>0.05). All the 48 patients were followed up with an average time of (6.6±0.5) months. All the incisions healed at grade A after operation, and no re-fracture of diseased vertebrae or adjacent vertebrae was found at the final follow-up. CONCLUSION: VBS system and PKP combined with zoledronic acid in the treatment of OVCFs not only may effectively relieve the pain in the thoracolumbar back, improve the mobility of the thoracolumbar, but also can restore the height of the vertebral body to the maximum extent, and prevent the re-fracture of the affected vertebrae and adjacent vertebrae, which is worthy to spread in clinic.

Double calcaneal osteotomy for severe adolescent flexible flatfoot reconstruction.

BACKGROUND: The timing and strategy of treatment for flatfoot still remain controversial. It is a difficult problem when facing severe adolescent flexible flatfoot because a single procedure cannot realign flatfoot deformity effectively. METHODS: We reviewed 13 adolescent flexible flatfoot patients who underwent double calcaneal osteotomy during May 2012 to June 2015. The mean age of patients was 15.2 ± 1.8 (range, 10-18) years. The American Orthopaedic Foot and Ankle Society Ankle-Hindfoot (AOFAS-AH) scores and SF-36 score were adopted to evaluate the preoperative and postoperative functions of the foot. Changes of hindfoot valgus angles, talonavicular uncoverage angles on AP view and talo-first metatarsal angles, and talar pitch angles and calcaneal pitch angles on the lateral film before and after surgery were measured. RESULTS: All 13 patients (15 ft) were followed. The mean duration of follow-up was 34.5 ± 15.7 (range, 21-60) months. The hindfoot valgus angle improved from 16.5 ± 4.1 to 2.9 ± 1.6. On the foot AP view, the mean preoperative and postoperative talonavicular coverage angles were 24.9 ± 8.5 and 6.5 ± 3.6. On the lateral view of the foot, the average preoperative and postoperative talo-first metatarsal angles were 18.1 ± 5.5 and 4.9 ± 4.4. The mean preoperative and postoperative talar pitch angles were 36.4 ± 4.7 and 24.0 ± 5.6. The AOFAS-AH score improved from 68.9 ± 12.3 preoperatively to 94.6 ± 3.9 postoperatively. CONCLUSION: With additional procedures, double calcaneal osteotomy was an effective method for severe adolescent flexible flatfoot.

Joint-Preserving Surgery for Talar Malunions or Nonuions.

OBJECTIVE: To describe the technique and analyze the outcomes of joint-preserving surgical treatments which included anatomical reconstruction or alignment correction for talar malunions or nonunions, and avoid development of degenerative changes in the adjacent joints. METHODS: Eight patients who had painful talar malunions or nonunions treated between 2009 and 2015 were included in this retrospective study. The mean age of the patients was 35.6 years, with patients aged from 18 to 58 years. Two patients had talar neck fractures and six had talar body fractures. According to a classification of post-traumatic talar deformities, five patients were classified as type I (malunion and/or residual joint displacement), two as type II (nonunion with displacement), and one as type III (malunion with partial avascular necrosis [AVN]). Of these patients, six cases were treated with an osteotomy through the malunited fracture or removal of the pseudarthrosis, and two cases were corrected by supramalleolar or calcaneal osteotomies owing to complete disappearance of the former fracture lines. The follow-up evaluation methods included the 36-Item Short Form Health Survey (SF-36) score, the American Orthopaedic Foot and Ankle Society (AOFAS) score, range of motion (ROM), and radiological analysis. The differences between postoperative scores and preoperative scores were evaluated statistically with the paired Student's t-test. Significance was assumed at P < 0.05. RESULTS: The mean follow-up time was 25.6 months. No wound healing problems or infections were observed. Solid union was obtained without redislocation in all cases, and with no signs of development or progression of AVN. At a mean of 25.6 months (range, 16-36 months) after reconstruction, all patients were satisfied with the result. The mean AOFAS score increased from 30.0 ± 7.0 pre-operatively to 86.5 ± 7.8 post-operatively (P < 0.001), the mean SF-36 score increased from 38.8 ± 4.1 to 81.4 ± 7.7 (P < 0.001), and the average ROM (tibiotalar joint) increased from 40.5° ± 8.7° to 43.9° ± 7.2° (P < 0.05). DISCUSSION: Joint-preserving procedures for talar malunions or nonunions can bring about satisfactory outcomes, and the appropriate procedure should be adopted according to different types of post-traumatic deformities.

Realignment Surgery for Malunited Ankle Fracture.

OBJECTIVE: To investigate the characteristics and the results of realignment surgery for the treatment of malunited ankle fracture. METHODS: Thirty-three patients with malunited fractures of the ankle who underwent reconstructive surgery at our hospital from January 2010 to January 2014 were reviewed. The tibial anterior surface angle (TAS), the tibiotalar tilt angle (TTA), the malleolar angle (MA), and the tibial lateral surface angle (TLS) were measured. Clinical assessment was performed with use of the American Orthopaedic Foot and Ankle Society (AOFAS) scale and visual analogue scale (VAS) scores, and the osteoarthritis stage was determined radiographically with the modified Takakura classification system. The Wilcoxon matched-pairs test was used to analyze the difference between the preoperative and the postoperative data. RESULTS: The mean follow-up was 36 months (range, 20-60 months). The mean age at the time of realignment surgery was 37.1 years (range, 18-62 years). Compared with preoperation, the TAS at the last follow-up showed a significant increase (88.50° ± 4.47° vs. 90.80° ± 3.49°, P = 0.0035); similar results were observed in TTA (1.62° ± 1.66° vs. 0.83° ± 0.90°, P < 0.01) and MA (82.30° ± 8.03° vs. 78.70° ± 4.76°, P = 0.005). At the last follow-up, the mean AOFAS score was significantly increased compared with the score at preoperation (44.5 ± 13.7 vs. 78.0 ± 8.9, P < 0.01). Significant differences in VAS scores were found at the last follow-up (6.76 ± 1.03 vs. 2.03 ± 1.21, P < 0.01). There was no significant difference in the Takakura grade between the preoperation and the last follow-up. One patient had increased talar tilt postsurgery; the postoperative talar tilt angle of this patient was 20°. One patient had progressive ankle osteoarthritis, and was treated by ankle joint distraction. CONCLUSIONS: Realignment surgery for a malunited ankle fracture can reduce pain, improve function, and delay ankle arthrodesis or total ankle replacement. Postoperative large talar tilt and advanced stages of ankle arthritis are the risk factors for the surgery.

Calcaneal Z Lengthening Osteotomy Combined With Subtalar Arthroereisis for Severe Adolescent Flexible Flatfoot Reconstruction.

BACKGROUND: The timing and strategy for operative treatment of flatfoot are still controversial. The purpose of this study was to evaluate clinical outcomes and radiographic changes following calcaneal Z osteotomy combined with subtalar arthroereisis for severe adolescent flexible flatfoot. METHODS: Data were analyzed for 16 patients (20 feet) who had flatfoot without tibialis posterior tendon dysfunction and were treated by calcaneal Z osteotomy combined with arthroereisis between October 2011 and February 2015. The mean age of patients at the time of surgery was 12.8 ± 1.4 years (range, 10-14 years). Preoperative and postoperative measurements included changes in hindfoot valgus angles; changes in talonavicular uncoverage angles on anteroposterior (AP) radiographic view; and changes in talo-first metatarsal angles, talar pitch angles, and calcaneal pitch angles on lateral radiographic view. The American Orthopaedic Foot & Ankle Society Ankle-Hindfoot Score (AOFAS-AH) was used to assess foot function. The mean follow-up was 18.9 ± 6.9 months (range, 13-33 months). RESULTS: The hindfoot valgus angle improved from 14.9 ± 4.2 degrees to 2.3 ± 1.7 degrees. On the AP view, the preoperative and postoperative talonavicular uncoverage angles were 30.5 ± 9.4 degrees and 9.8 ± 4.8 degrees, respectively. On lateral radiographs, the preoperative talo-first metatarsal angle, talar pitch angle, and calcaneal pitch angle were -22.1 ± 7.9 degrees, 36.1 ± 4.4 degrees, and 14.4 ± 4.0 degrees, respectively. Postoperative lateral radiographs demonstrated talo-first metatarsal angle, talar pitch angle, and calcaneal pitch angle of -6.2 ± 4.7 degrees, 27.3 ± 4.9 degrees, and 19.0 ± 4.3 degrees, respectively. The AOFAS-AH score improved from 66.8 ± 24.1 preoperatively to 96.5 ± 3.4 postoperatively. CONCLUSIONS: For adolescents with flatfoot, calcaneal Z osteotomy combined with subtalar arthroereisis provided satisfactory results. LEVEL OF EVIDENCE: Level IV, retrospective case series.

Recent Advances in Foot and Ankle Surgery in Mainland China: Correction of Severe Foot and Ankle Deformities.

Foot and ankle physicians in China encounter quite a large amount of severe and complex deformities. The main cause of severe ankle and foot deformity is trauma, while the other causes may be neuromuscular diseases, improper reduction and fixation and so on. Staged procedure may sometimes be a safer way to correct deformities in the presence of severe soft tissue contracture. Periarticular osteotomy combined with soft tissue balancing can be used in treating severe varus ankle arthritis, including stage IIIb cases and patients with talar tilt of more than 10 degrees.

Redefining the Vascular Classifications of the Lateral Supramalleolar Flap.

BACKGROUND: The blood supply of the lateral supramalleolar flap (LSMF) generally comes from the perforating branch of the peroneal artery. However, the cutaneous branch may also receive blood from the anterior tibial artery. The main objective of the present study was to clarify the vascular anatomy of the LSMF. METHODS: Anatomical dissections were performed on 28 perfused fresh cadaver legs. The cutaneous branches of LSMF were identified, and the anatomic relationship between the cutaneous branches and the peroneal and anterior tibial arteries was analyzed. RESULTS: The vascular supply for LSMF was divided into 2 main types. A collateral inferolateral branch from the anterior tibial artery anastomosed with the perforating branch of the peroneal artery around the inferior tibiofibular angle, and the main cutaneous branch of the flap arose from this arterial anastomosis in 20 of 28 limbs (71.4%). The collateral inferolateral branch was absent or very small in the other 8 of 28 dissections (28.6%), and the cutaneous branches solely arose from the perforating branch of the peroneal artery. The anastomosis of the descending branch of the peroneal artery and anterior lateral malleolar artery was always (100%) found around the tibiotalar joint. CONCLUSIONS: In addition to the perforating branch of the peroneal artery, the LSMF may also receive blood from the anterior tibial artery through the collateral inferolateral branch. New modified proximally based flaps could be designed, and caution is warranted for these variations when a distally based flap is performed.

Comparison of the efficacy of three isolated gastrocnemius recession procedures in a cadaveric model of gastrocnemius tightness.

PURPOSE: Many surgical techniques for isolated gastrocnemius recession have been described. The purpose of the present study is to compare their therapeutic efficacy and intrinsic stability on a fresh cadaveric model of gastrocnemius tightness. METHODS: The cadaveric model was established by distracting the knee with spacers composed of low-temperature thermoplastic material, and was identified by the Silfverskiöld test. Procedures of gastrocnemius recession described by Barouk, Baumann and Strayer were performed. The lengthening distance and improvement of ankle dorsiflexion were measured. RESULTS: The mean ankle angle of the cadaveric models was -15.4° with the knee fully extended, and 8.4° with the knee flexed. The increased angle achieved by the Strayer procedure was significantly greater than that achieved by the Barouk procedure and the Baumann procedure with one cut (P < 0.05), but similar to that of the Baumann procedure with two cuts (P > 0.05). Compared with the intramuscular lengthening of the gastrocnemius (Baumann and Barouk procedures), the stability of the lengthening after the Strayer procedure was the lowest. CONCLUSION: The three techniques of isolated gastrocnemius recession have different efficacy and stability in cadaver trials, depending on their own anatomical characteristics. Our study supplies an anatomical guide for the selection of a proper procedure.

[Review on biological treatment of cyanobacterial toxin in natural waters]. / çŽ¯å¢ƒæ°´ä½“è—»æ¯’ç´ ç”Ÿç‰©å¤„ç†æŠ€æœ¯ç ”ç©¶è¿›å±•.

In recent years, eutrophication has not been effectively controlled and algal pollution still breaks out frequently. At the same time, the cyanobacteria and release of algal toxins have posed a serious threat to the environment and human health. In this review, the classification and main physicochemical properties of algal toxins were summarized, and the biological removal strategies of algal toxins including biological contact oxidation process, biological filter process and biological ecological coupling process and their biodegradation mechanisms were reviewed. The influence factors on biological treatment process, including operation conditions (temperature, pH and hydraulic retention time), water property and nutrient limitation factors, were analyzed. The research on the removalmechanisms of other algae toxins and the development and optimization of new biological technology were prospected to develop and improve algal toxin removal technology and ensure drin-king water safety.

Mid-term Results of Intramuscular Lengthening of Gastrocnemius and/or Soleus to Correct Equinus Deformity in Flatfoot.

BACKGROUND: Intramuscular lengthening of the gastrocnemius and/or soleus (Baumann procedure) is widely used in patients who have cerebral palsy, with several advantages over other lengthening techniques. Tightness of the gastrocnemius or gastrocnemius-soleus complex has been confirmed to be related to flatfoot deformity. The purpose of this study was to evaluate the mid-term results of the Baumann procedure as a part of the treatment of flatfoot with equinus deformity. METHODS: We reviewed 35 pediatric and adult patients (43 feet) with flatfoot who underwent the Baumann procedure for the concomitant equinus deformity. The mean duration of follow-up was 39.4 months. Preoperative and follow-up evaluations included the maximal angle of dorsiflexion of the ankle with the knee fully extended and with the knee flexed to 90 degrees, the American Orthopaedic Foot & Ankle Society ankle-hindfoot (AOFAS-AH) scores, and postoperative complications. RESULTS: Preoperatively, the mean angle of passive ankle dorsiflexion with the knee extended was -4.7 ± 2.7 degrees and that with the knee flexed was 2.3 ± 2.5 degrees. At the final follow-up, both values improved significantly by a mean of 13.6 degrees (P < .001) and 9.7 degrees (P < .001), respectively. The average AOFAS-AH scores improved from 56.8 points preoperatively to 72.1 at the final follow-up. Recurrence of equinus was observed in 3 patients (4 feet). There were no cases of overcorrection, neurovascular injury, or healing problems. CONCLUSIONS: Our results indicate that the Baumann procedure can effectively and sequentially correct the tightness of the gastrocnemius or the gastrocnemius-soleus complex in patients with flatfoot deformity, without obvious postoperative complications. LEVEL OF EVIDENCE: Level IV, retrospective case series.

Performance and enhanced mechanism of a novel bio-diatomite biofilm pretreatment process treating polluted raw water.

A lab-scale novel bio-diatomite biofilm process (BDBP) was established for the polluted raw water pretreatment in this study. Results showed that a shorter startup period of BDBP system was achieved under the completely circulated operation mode, and the removal efficiencies of nitrogen and disinfection by-product precursor were effective at low hydraulic retention time of 2-4 h due to high biomass attached to the carrier and diatomite. A maximum NH4(+)-N oxidation potential predicted by modified Stover-Kincannon model was 333.3 mg L(-1) d(-1) in the BDBP system, which was 4.7 times of that in the control reactor. Results demonstrated that the present of bio-diatomite favors the accumulation of functional microbes in the oligotrophic niche, and the pollutants removal performance of this novel process was enhanced for polluted raw water pretreatment.

Removal performance of nitrogen and endocrine-disrupting pesticides simultaneously in the enhanced biofilm system for polluted source water pretreatment.

The removal performances of nitrogen and trace levels of endocrine-disrupting pesticides (cypermethrin and chlorpyrifos) were studied in the enhanced biofilm pretreatment system at various substrates concentrations and dissolve oxygen (DO) niches. No significant change of EDPs removal occurred with the increased feed of ammonia nitrogen in aerobic batch tests or nitrate in anaerobic batch reactors, but significantly enhanced via reed addition both in aerobic and anaerobic conditions. Simultaneously enhanced denitrification and EDPs removal were achieved in the anoxic niche with reed addition. The results of denaturing gradient gel electrophoresis (DGGE) indicated that new bands appeared, and some bands became more intense with the reed addition. Sequences analysis showed that the dominant species belonged to Methylophilaceae, Hyphomicrobium, Bacillus and Thauera, which were related to the nitrogen or EDPs removals. In addition, the growth of functional heterotrophic microbes may be promoted via reed addition.