• Journal of the Korean Arthroscopy Society
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• v.6 no.2
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• pp.188-191
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• 2002

The complication caused by a bioabsorbable interference screw composed of Poly-L-Lactic-Acid is rare after anterior cruciate ligament (ACL) reconstruction. We reported a case of a pretibial ganglion at the orifice of the tibial tunnel where the graft tendon had been fixed with a bioabsorbable interference screw $(Bioscrew^{\circledR})$ for ACL reconstruction using autogenous hamstring tendon. The patient was underwent ganglion excision and interference screw removal.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.9 no.3
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• pp.169-177
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• 2000

In machining screws which are important members in mono pumps or progressive cavity pumps CNC turning center with 3 axes is usually used. This sort of screw machining requires large amount of CL data points and rotational tools are used in machining. When working out the CL data points consideration of possible tool interference is important in order to avoid undercut. This paper describes the checking methods of tool interference in the screw machining on the CNC turning center. First of all a specific shape of a screw cross-section that could commonly be applied to all screws was chosen and then possible tool interference associated with that shape was identified. Checking method was mathematically developed and verified. This checking method will be utilized in the CAM system developed by the authors for screw machining on the 3-axis CNC turning center.

• Journal of the Korean Arthroscopy Society
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• v.2 no.1
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• pp.85-92
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• 1998

Various methods for fixation of graft have been widely used for reconstruction of anterior cruciate ligament. However, the biomechanical strength of each fixation techniques are not fully understood. The purpose of this study is to compare the pull out strength of different fixation techniques which is probably the most important factor for the success at the initial stage of healing. Biomechanical test was carried out to measure and compare the pull out tensile strength of five different fixation techniques in 35 pig(Yorkshire) knees. ANOVA and Duncan multiple comparison test was applied for statistical analysis. In the two fixation techniques with bone patellar tendon bone graft, the mean maximum tensile strength was $1333.4{\pm}148.5N$ with titanium interference screw, while it was $1310.1{\pm}168.9N$ with biodegradable interference screw. The failure mode were pulled out of bone plugs from the femoral tunnel in majority cases. In the fixations with hamstring tendon, the mean maximum tensile strength were $1405.9{\pm}135.1N$ with SemiFix screw, $820.3{\pm}104.5N$ with biodegradable interference screw, and $682.1{\pm}54.2N$ with Endobutton. The mode of failure was variable in each technique. The tendon was pulled out from the tunnel in biodegradable interference screw fixation, the screw was bent in the SemiFix system, and the polyester tape were ruptured or the buttons were pulled into tunnel in Endobutton fixation. The mean maximum tensile strength of two interference screws with bone patellar tendon bone was statistically comparable to that of SemiFix with hamstring tendon. However biodegradable interference screw and Endobutton with hamstring tendon showed weaker maximum tensile strength than above three fixation techniques (P<0.05).

• Journal of the Korean Arthroscopy Society
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• v.10 no.1
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• pp.87-90
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• 2006

The complication caused by a bioabsorbable interference screw is rare after anterior cruciate ligament reconstruction. We report a case of delayed inflammatory reaction at the tibial tunnel and femoral tunnel where the graft tendon had been fixed with a bioabsorbable interference screw ($Bioscrew^{(R)}$) for anterior cruciate ligament reconstruction using bone-patellar tendon-bone autograft.

• Journal of the Korean Arthroscopy Society
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• v.10 no.2
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• pp.187-191
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• 2006

Few cases have been reported in which the femoral interference screw has migrated into the posterior compartment after an ACL reconstruction. It usually requires removal, because it leads usually to mechanical symptom. However, the arthroscopic removal of a screw is a technically demanding procedure, especially in the case of an intact integrated ACL graft or one that is encapsulated around the screw. We present a case in which a displaced femoral interference screw migrated within the posterior compartment 11 years postoperatively, after the graft had been successfully incorporated at the femoral site and showed good continuity on MRI and arthroscopic examination. Although it is often technically challenging, through the use of a posterior trans-septal portal, we can successfully remove a displaced femoral interference screw even in the most difficult locations in the posterior compartment without damage to ACL graft.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.1
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• pp.11-18
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• 2011

A worm screw is widely used in a geared motor unit for motion conversion from rotation to linear. For mass production of a high quality worm, the current rolling process is substituted with the milling process. Since the milling process enables the integration of all operations of worm manufacturing on a CNC(Computer Numerical Control) lathe, productivity can be remarkably improved. In this study, the tooling system for side milling on a CNC lathe to improve machinability is developed. However, the cutting tool-workpiece interference is important factors to be considered for producing high quality worms. For adaptability of various worms machining, the tool-workpiece interference simulation system based on a tool-tip trajectory model is developed. The developed simulation system is verified through several kinds of worms and experimental results.

• Journal of the Korean Society for Precision Engineering
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• v.26 no.12
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• pp.47-54
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• 2009

A worm screw is widely used in a geared motor unit for motion conversion from rotation to linear. For mass production of a high quality worm, the current rolling process is substituted with the milling process. Since the milling process enables the integration of all operations of worm manufacturing on a CNC(Computer Numerical Control) lathe, productivity can be remarkably improved. In this study, the tooling system for planetary milling on a CNC lathe to improve machinability is developed. However, the cutting tool-workpiece interference is important factors to be considered for producing high quality worms. For adaptability of various worms machining, the tool-workpiece interference simulation system based on a tool-tip trajectory model is developed. The developed simulation system is verified through several kinds of worms and experimental results.

• Journal of the Korean Arthroscopy Society
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• v.6 no.1
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• pp.60-63
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• 2002

Purpose : The purpose of this study was to introduce new femoral fixation technique using a cross-pin and a bioabsorbable interference screw in hamstring ACL reconstruction. Method : Semitendinosus and gracilis were harvested for quadrapled graft. After tibial tunnel had been made, femoral tunnel was made 35 mm in depth. Then the graft passed through the tunnels. Cross-pin was fixed through the drill hole which had been made through upper sleeve of the Rigidfix system. While pulling the graft, bioabsorbable interference screw was fixed through the anteromedial portal. Conclusion : We introduced the new femoral fixation technique using a cross-pin and a bioabsorbable interference screw as a good method with high fixation strength and tight graft-bone contact.

• Clinics in Shoulder and Elbow
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• v.16 no.2
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• pp.94-99
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• 2013

Purpose: The purpose of this study is to evaluate the clinical results of arthroscopic biceps long head suprapectoral tenodesis using an interference screw. Materials and Methods: We reviewed the cases of 30 patients who underwent arthroscopic biceps long head suprapectoral tenodesis using an interference screw between January 2008 and January 2010. The minimum follow up period was one year. Twenty patients had rotator cuff tears. The results were analyzed by VAS, ASES, tenderness in the bicipital groove, fixation failure, and the degree of deformity. Results: VAS, ASES scores showed a statistically significant increase during the final observation in all patients, compared with those before surgery. However, five patients (17%) had anterior shoulder pain and tenderness in the biceps groove, and three patients (10%) had Popeye deformity. Better results were achieved in patients without rotator cuff tear than in patients with rotator cuff tear (p<0.05). Conclusion: Arthroscopic biceps long head tenodesis above the pectoralis major using an interference screw in patients with a pathologic lesion of the proximal biceps tendon showed good results at the last follow up. However, further study for tenderness in the biceps groove in 17% of patients is needed.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.33 no.4
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• pp.430-439
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• 2009

Posterior Cruciate Ligament (PCL) plays an important role in knee extension. Rotational instability due to injured PCL can be restored by various PCL reconstruction methods. In this study, the initial lengthening affected by fixation device and location was demonstrated, and furthermore, the slippage and the relationship between lengthening ratio and slippage ratio in the calcaneus and soft tissue fixation methods was newly suggested. Eight specimens of proximal tibia and Achilles tendon grafts were harvested from four cadavers and divided into four groups in regard to the four different types of transtibial fixation techniques. The cyclic load ranged from 50 N to 250 N applied to each graft fixed to proximal tibia in 55 degrees. The initial lengthening ratio to the total elongation has been approximately constant regardless of the fixation methods. The soft tissue fixation method with an interference screw showed about 56.4% slippage ratio to the total elongation and the same method with a double cross-pin presented about 45.4% slippage ratio. The soft tissue fixation method with an interference screw demonstrated approximately 2 mm less total elongation and about 13% more slippage than lengthening because of poor fixation compared to the same method with a double cross-pin.