Examination of radioulnocarpal joint loading after radial shortening osteotomy for the treatment of Kienböck's disease (Biomechanical study)

Radial kısaltma osteotomisi, Kienböck hastalığı ve negatif ulnar varyans varlığında, radiolunat ekleme binen yükü azalttığı için uygulanan bir yöntem olarak bilinmektedir. Radial kısaltma osteotomisinin, nötral veya pozitif ulnar varyanslı ve ileri evre Kienböck hastalıklı hastalarda da iyi klinik sonuçlar vermesi nedeniyle, radiolunat ekleme binen yük dağılımlarını azaltmak dışında, farklı bir mekanizma ile etkili olduğunu düşünüyoruz. Bu nedenle, radial kısaltma osteotomisinin, radiolunat eklem yük dağılımı üzerindeki etkilerini araştırmak amacıyla bu çalışmayı gerçekleştirdik. Bu biyomekanik çalışmada, sert köpükten imal edilmiş standart sol el bileği modelleri kullanıldı (Sawbones®, Malmö, Sweden). El bileği nötral pozisyonunda, sağlam el bileği modellerinde ve iki mm ve dört mm radial kısaltma osteotomisi uygulanan el bileği modellerinde, 14kgf ve 25kgf yüklenmeler altında, radioulnokarpal eklem yük dağılımları araştırıldı. Sağlam el bileği modellerinde, 14kgf ve 25kgf yüklenme sonrası oluşan ortalama basınç dağılımları karşılaştırıldığında, ulnokarpal eklemdeki artış, radiolunat eklemdeki azalma istatistiksel olarak anlamlı bulundu (sırasıyla, p=0,012, p=0,036). Hem 14kgf, hem de 25kgf yüklenme sonrası oluşan ortalama basınç dağılımları kendi aralarında karşılaştırıldığında, sağlam el bileği ve osteotomi yapılan gruplar arasında anlamlı fark saptanmadı. Sonuç olarak, radial kısaltma osteotomisi, el bileği nötral pozisyonunda, radiolunat ekleme binen yükleri azaltmada etkili değildir Anahtar kelimeler: Kienböck hastalığı, radial kısaltma osteotomisi, biyomekanik, radioulnokarpal yük dağılımı Radial shortening osteotomy is a well known applied technique for unloading radiolunate joint in cases of Kienböck's disease and negative ulnar variance. Radial shortening osteotomy provides good clinical results in neutral or positive ulnar variances and advanced stage Kienböck's disease cases. We think another mechanism is effective in radial shortening osteotomy rather than the radiolunate joint unloading. Therefore, in this study we aimed to show the effects of radial shortening osteotomy on the radiolunate joint load distribution In this biomechanical study, we used standart left wrist models made of solid foam (Sawbones®, Malmö, Sweden). The radioulnocarpal joint load distribution was investigated in normal wrist model and 2mm and 4mm radial shortening osteotomy models under 14kgf and 25kgf loads when the wrist position was neutral In the normal wrist group, the comparison of the average pressure distributions under the loads of 14kgf and 25kgf shows that the increase at the ulnocarpal joint loading and the decrease at the radiolunate joint loading were statistically significant (p=0,012, p=0,036, respectively). When we compare the respective average pressure distributions after 14kgf and 25 kgf loading, there were no statistically significant difference between the normal wrist and the osteotomy groups Consequently, radial shortening osteotomy is not effective to decrease the radiolunate joint loading when the wrist is in neutral position Key words: Kienböck's disease, radial shortening osteotomy, biomechanics, radioulnocarpal joint loadin

Retrospective comparison of open and percutaneous repair methods in acute achilles- tendon repair

Purpose: In recent years Achilles’ tendon tears are becoming more common. Open and percutaneous repair methods have been described in the surgical treatment of tendon tears. The aim of this study is to determine whether there is a difference between open repair and percutaneous repair. Methods: Patients who underwent surgical repair due to acute Achilles’ tendon full-thickness rupture in our clinic, were included in the study. Open repair was performed for one group of patients and percutaneous repair was performed for the other. At the end of follow-up, clinical scores and complication rates were compared statistically. Results: Thirty-six patients with a mean age of 46.3 years were included in the study. Nineteen patients were treated with the open method and seventeen patients with the percutaneous method. The mean follow-up period was 27.3 months for both groups. Mean Leppilahti scores were 94.71 in the percutaneous repair group and 90.79 in the open repair group (p>0.05). Re-rupture, deep infection and DVT rates were similar (p>0.05). Skin necrosis was more common in the open repair group (p<0.05). While sural nerve neuropraxia was more common in percutaneous repair (p<0.05). Conclusion: In the surgical treatment of acute Achilles’ tendon tears, the percutaneous method should be the first choice with its low complication rate and good clinical results. It is necessary to pay attention to the sural nerve during surgery

Chitosan-immobilized pumice for the removal of As(V) from waters

A novel sorbent, chitosan-immobilized pumice, has been prepared for the sorption of As(V) from waters prior to its determination by hydride generation atomic absorption spectrometry. The success of the immobilization has been checked with such characterization techniques as scanning electron microscopy, thermal gravimetric analysis, and elemental analysis. Points of zero charge of the sorbents were determined with potentiometric mass titration. Batch-type equilibration studies have shown that the novel sorbent can be employed at a wide pH range resulting in quantitative sorption (>90 %) at pH 3.0-7.0 and greater than 70 % sorption at pH >8.0. These results demonstrate the advantage of immobilizing chitosan onto pumice, because, under the same conditions, pumice displays <20 % sorption toward As(V), whereas chitosan gives approximately 90%sorption only at pH 3.0. The validity of the method was verified through the analysis of ultrapure, bottled drinking, and tap water samples spiked with arsenate; the respective sorption percentages of 93.2 (±0.7), 89.0 (±1.0), and 80.9 (±1.3) were obtained by batch-type equilibration. Arsenic sorption was also examined in the presence of common interfering ions resulting in competing effects of PO3- 4 and NO- 3on As(V) adsorption

Comparison of Open Reduction and Internal Fixation With Minimally Invasive Plating in the Treatment of Distal Tibial Fractures: A Retrospective Study

Introductio

Investigation of radioulnocarpal joint load distribution effects of radial shortening osteotomy for the treatment of Kienbock disease: a biomechanical study

Objectives: We evaluated the effects of radial shortening osteotomy on the radiolunate joint load distribution