Learning curve of the Krackow suture technique for the repair of Achilles tendon rupture.

INTRODUCTION: Knowledge on the learning curve for the repair of Achilles tendon rupture is limited. The aim of this study was to quantify the learning curve for the Krackow suture technique for the repair of Achilles tendon rupture and to identify the correlation between the cumulative volume of cases and clinical outcome measures. MATERIALS AND METHODS: A total of 226 cases of Achilles tendon repair using the Krackow suture technique were reviewed. Each surgery was independently performed by four surgeons who started a foot and ankle specialty career after fellowship training. After logarithmic transformation of the operative time and cumulative volume of cases, a linear regression analysis was performed to determine the best-fit linear equations to predict the required time for the Krackow suture technique according to the cumulative volume of cases. The correlation between the cumulative volume of cases and clinical outcome measures was analyzed using Pearson correlation coefficients. Receiver operating characteristic curves were constructed to determine the minimum number of cases with an operative time shorter than the average in the first 30 cases. RESULTS: In all four surgeons, significant log-linear correlations were observed between the operative time and cumulative volume of cases. The best-fit linear equations showed estimated learning rates of 90%, 87%, 92%, and 86% for each of the four surgeons, indicating that the necessary operative time decreased by 10%, 13%, 8%, and 14%, respectively, when the cumulative volume of cases had doubled. The minimum number of cases with an operative time shorter than the average was 9 (91% sensitivity and 59% specificity). The clinical outcome measures at 6 and 12 months postoperatively were available for one surgeon; however, no correlation was found with the cumulative volume of cases. CONCLUSION: The learning rate for the Krackow suture technique for the repair of Achilles tendon rupture was approximately 89%, indicating that the required operative time can decrease by up to 11% when the cumulative volume of cases doubles. Therefore, it is important to rapidly accumulate surgical experience during the early phase of training.

Comparison of Outcome of Deltoid Ligament Repair According to Location of Suture Anchors in Rotational Ankle Fracture.

BACKGROUND: The suture anchors for the repair of deltoid ligament in rotational ankle fracture are inserted mostly into the medial malleolus, but sometimes are placed into the talus depending on the rupture site. This study sought to compare the radiological and clinical outcomes of deltoid ligament repair according to using these 2 locations for suture anchor placement. METHODS: The cases of 131 patients (114 patients with suture anchors on the medial malleolus and 17 patients with suture anchors on the talus) who underwent deltoid ligament repair along with ankle fracture fixation were retrospectively reviewed. Medial clear space oblique (MCSo), medial clear space perpendicular (MCSp), tibiofibular clear space (TFCS), and tibiofibular overlap (TFO) were measured as radiological outcomes, while the Olerud-Molander Ankle Score (OMAS) and visual analog scale (VAS) score for pain were calculated as clinical outcomes. The follow-up period did not differ between the 2 groups (16.8 ± 10.9 months in the medial malleolus group vs 17.9 ± 14.3 months in the talus group; P = .670). RESULTS: There were no differences in MCSo, MCSp, TFCS, and TFO at 3 months after surgery and final follow-up. The OMAS and VAS for pain did not show intergroup differences at final follow-up. CONCLUSION: The surgical outcome of deltoid ligament repair in rotational ankle fracture did not differ whether the suture anchors were inserted into the medial malleolus or into the talus. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Comparison of clinical and radiologic outcomes between non-operative and operative treatment in 5th metatarsal base fractures (Zone 1).

The treatment of Zone 1 fractures of the 5th metatarsal base with >2mm of displacement remains controversial. We prospectively analyzed 29 patients with 5th metatarsal base fractures (Zone 1) during 2009-2014. Radiography was performed to assess the degree of fracture gap and metatarsal length. Patients with gaps of 2mm or less were treated conservatively using a short leg cast or splint (Group A), while patients with fracture gap >2mm were randomly assigned to one of two groups. Group B patients were managed with open reduction and internal fixation (ORIF), and Group C patients were placed in a short leg cast only. Visual analog scale (VAS) score and American orthopedic foot and ankle society (AOFAS) score were obtained at the initial consult and at the last follow-up after treatment; change of the 5th metatarsal length was also measured at the initial consult and after complete bony union. Our study demonstrated that radiographic union of all cases was observed with a significant decrease in VAS and AOFAS scores, regardless of the initial fracture gap and type of management. Additionally, there was no difference seen in final VAS scores for patients with longer metatarsals when compared to those in whom the metatarsals were unchanged or shortened.

The contribution of anterior deltoid ligament to ankle stability in isolated lateral malleolar fractures.

The treatment of isolated lateral malleolar fractures with deltoid ligament rupture remains controversial. We prospectively analysed 35 patients with isolated lateral malleolar fractures during 2006-2013. Radiography and magnetic resonance imaging (MRI) were performed to assess the degree of reduction, ligament damage, and stability. Internal fixation was performed for all unstable valgus fractures with unacceptable fracture parameters. Fractures with residual valgus instability after fixation underwent anterior deltoid repair. The mean anterior deltoid ligament grade based on MRI was significantly different between the high-grade unstable group and the stable and low-grade unstable groups (p=0.037 and 0.004, respectively). Postoperative medial clear space measurements were not significantly different between groups. MRI was shown to be a useful tool in the preoperative identification of isolated lateral malleolus fractures prone to valgus instability. In the case of high-grade unstable fractures of the lateral malleolus, repair of the anterior deltoid ligament is adequate for restoring medial stability.

Clinical effectiveness of wireless CROS (contralateral routing of offside signals) hearing aids.

This study evaluated the clinical effectiveness of wireless contralateral routing of offside signals hearing aids (CROS) in patients with severe to profound unilateral sensorineural hearing loss (USNHL). Twenty-one patients with USNHL were enrolled in this prospective study. The change of subjective satisfaction was evaluated using three questionnaires (K-HHIE, K-IOI-HA, K-SSQ). Changes in objective measurements were evaluated with sound localization test (SLT) and hearing in noise test (HINT). These tests were performed at pre-CROS fitting, 2 and 4 weeks after use of CROS. Subjects were grouped according to the age: young (<40 years) vs. old (≥40 years) group. The average K-HHIE and K-SSQ scores significantly improved with the use of CROS. SLT result revealed that hit rate and error degree improved in the young group and lateralization ability improved in both groups. In quiet environments, the reception threshold for speech also indicated a significant benefit in the young group. When the noise was presented to the normal ear, HINT revealed benefit of CROS, while loss of performance with CROS use was significant when noise was presented to the impaired ear. Wireless CROS provided increased satisfaction and overall improvement of localization and hearing. Although true binaural hearing cannot be obtained, CROS is a practical option for rehabilitation of USNHL.

Comparison of adenoid cystic carcinomas arising from the parotid gland vs. the submandibular gland: focus on systemic metastasis and tumor-associated blood vessels.

BACKGROUND: Although several studies reported that distant metastasis occurs more frequently in the tumors of submandibular gland (SMG) than parotid gland (PG), why SMG tumors preferentially metastasize to distant organs is not fully understood. We aimed to identify the differential tumor microenvironment for distant metastasis and possible underlying mechanisms. METHODS: We retrieved 27 cases of 1-4-cm-sized adenoid cystic carcinomas (ACCs) arising from the PG (n = 12) and SMG (n = 15). c-KIT, VEGF-R2, and CD31 staining were quantified by image-based analysis to define the positive expression or tumor-associated vessel areas in two representative sections per case. In addition, angiogenesis-related genomic expression profiling was carried out to explore the underlying mechanism, which was confirmed by RT-PCR and immunohistochemistry. RESULTS: Earlier systemic dissemination within 2 years was detected exclusively in SMG ACCs (5/15). The area of tumor-associated blood vessels was larger in SMG ACCs than PG ACCs, and ACCs showing distant metastasis had greater blood vessel area than those without metastasis. Interestingly, normal SMG had more blood vessels per area than PG. Among angiogenesis-related signals, the level of IL-6 was significantly lower in SMG ACCs than PG ACCs. Moreover, IL-6 expression decreased significantly in SMG ACCs compared with that in normal SMG, whereas it was up-regulated in PG ACCs. CONCLUSION: ACCs in the SMG microenvironment have more abundant tumor-associated blood vessels than PG ACCs, which may explain the higher risk of distant metastasis from SMG tumors.