The Survivorship and Clinical Results of Minimally Invasive Unicompartmental Knee Arthroplasty at 10-Year Follow-up

BACKGROUND: In this study, we investigated the long-term clinical results and survival rate of minimally invasive unicompartmental knee arthroplasty (UKA) by collecting cases that had been implanted more than 10 years ago. METHODS: One hundred and twenty-eight patients (166 cases) who underwent Oxford phase 3 medial UKA using the minimally invasive surgery from January 2002 to December 2002 were selected. The mean age of the patients at the time of surgery was 61 years, and the duration of the follow-up was minimum 10 years. Clinical and radiographic assessments were performed using the Knee Society clinical rating system, and the survival analysis was done by the Kaplan-Meier method with 95% confidence interval (CI). RESULTS: The mean Knee Society knee and function scores improved significantly from 53.8 points (range, 25 to 70 points) and 56.1 points (range, 35 to 80 points) preoperatively to 85.4 points (range, 58 to 100 points) and 80.5 points (range, 50 to 100 points) at 10-year follow-up, respectively (p < 0.001). Failures following the UKA occurred in 16 cases (9.6%), and the mean time of the occurrence of the failure was 6.2 years after the surgery. The 10-year survival rate was 90.5% (95% CI, 85.9 to 95.0) when failure was defined as all the reoperations, whereas the 10-year survival rate was 93.4% (95% CI, 89.6 to 97.1) when the cases in which only revision total knee arthroplasty was defined as failure. CONCLUSIONS: The results of this study show outstanding functions of the knee joint and satisfactory 10-year survival rate after minimally invasive UKA. Therefore, minimally invasive UKA could be a useful method in the treatment of osteoarthritis in one compartment of knee joint.

"Delta(Delta) wire Technique" for Bony Mallet Finger: Surgical Technique / 대한정형외과연구학회지

Bony mallet finger is treated by from conservative management to various operative options. A lot of internal fixations except hook plate lead to cartilage damage and limitation of motion of distal interphalangeal joint. Thus we introduce Delta(Delta)-wire technique which can permit early joint motion and give strong compression force on the fracture fragment continuously.

Finite Element Analysis of Stress and Deformation according to the Shape of Plates for Internal Bone Fixation / 대한정형외과학회잡지

PURPOSE: To determine the metal plate that has almost the same volume and weight as the conventional plate, but has improved properties by changing the shape using finite element analysis. MATERIALS AND METHODS: The bone is assumed to be of 100 mm length, 20 mm outer diameter and 12 mm inner diameter, respectively. There is a fracture line that is perpendicular to the major axis of the bone at the center. The two pieces of bone are joined together using a metallic plate that is made of titanium. Six holes are located, with an interval of 12 mm. We suppose that screws of 2 mm diameter and 25 mm length are inserted in six holes. The metallic plates are of 5 shapes (A, B, C, D and E) in total. Shape A is the standard or nominal type. Shape B and C are thicker at the center of the plate, respectively. Shape D and E are wider at the center. Six types of load are applied to each of those plates: tension, compression, anterior flexion, posterior flexion, lateral flexion and torsion. We compared stress, deformation, maximal stress and maximal deformation, according to the six types of load. RESULTS: Our deliberate investigation using finite element analysis showed that increasing the thickness or width at the center of metallic plates lowered the maximum stress and deformation. In particular, maximal stress and deformation could be reduced by 33.5% and 38.6%, respectively, in the anterior bending situation. Compression showed lower stress and deformation in type C or D, but the absolute quantity was much smaller than others, for example 0.01-0.001 times. CONCLUSION: As for the internal bone fixation plates with the same volume, the wider or thicker in the middle the plate become, the less deformation and yielding it bears.

The Tourniquet Pressure 200 mmHg for Total Knee Arthroplasty: is it possible? / 대한정형외과연구학회지

PURPOSE: To evaluate the possibility of lowering tourniquet pressure to 200 mmHg during total knee arthroplasty (TKA) by pressing the femoral artery. Lowering the toniquette pressure can attribute to minimize the soft tissue damage and pain after the operation. MATERIALS AND METHODS: We analyzed patients who had TKA from Sep 16th, 2010 to Mar 3rd, 2011. Among them, 35 patients (test I) had operations on both knees, and 50 patients (test II) underwent operation on one knee. We excluded the patients who had a previous operation, infection, or bleeding tendency. We put a cotton roll at the antero-medial side of the thigh just under the tourniquet in order to apply more pressure on the femoral artery that is scanned by ultrasonography. We scored 0 on non-bleeding, 1 on bleeding that did not affect the operation, and 2 on bleeding which disturbed the operation. RESULTS: In test I, the group which applied 200 mmHg with local pressure, 24 patients (68.6%) scored 0, 9 patients (25.7%) scored 1, and two patients (5.7%) scored 2. In the other group used pressure 250 mmHg, however, 31 patients (88.6%) scored 0, 4 patients (11.4%) scored 1, and no one scored 2 (p=0.039). Totally, in the 200 mmHg group with local pressure, 33 patients had no problem in surgery, and only for 2 patients (5.7%), we had to increase pressure. For the patients with 250 mmHg, however, we had to increase pressure on nobody (0%). In test II, in the group which had operation on one knee with 200 mmHg with local pressure, 14 patients scored 0, 8 patients scored 1, and one patient scored 2. Also in the 250 mmHg group, 24 patients scored 0, 2 patients scored 1, and one patient scored 2. (p=1.000). Overall results demonstrate no differences in bleeding that disturb operations statistically. CONCLUSION: Even with a little more bleeding compared to the 250 mmHg group, 94.8% of patients can have operation with no bleeding problems by using a cotton roll and the pressure 200 mmHg. For successful operations, there is no difference between groups using 250 mmHg and 200 mmHg with local pressure on femoral artery.

Relationship between the Tourniquet Pressure and the Amount of Subcutaneous Bleeding after Total Knee Replacement

PURPOSE: We wanted to evaluate the post-operative amount of subcutaneous bleeding according to the tourniquet pressure during total knee replacement. MATERIALS AND METHODS: We analyzed 136 patients who had undergone total knee replacement at our hospital from March 4th, 2010 to September 16th, 2010. A tourniquet pressure of 250 mm Hg was applied to 69 patients (group I) and a tourniquet pressure of 320 mm Hg was applied to the other 67 patients (group II). Subcutaneous bleeding was evaluated on the 3rd and 6th days after the operations. All of the total knee replacements were performed by a single surgeon. RESULTS: Among the group I patients, subcutaneous bleeding was seen in just 2 patients, yet among the group II patients, there were 32 patients with subcutaneous bleeding on the 3rd day and 33 patients with subcutaneous bleeding on the 6th day. According to the multiple regression analysis, there were no significant differences in ages, the tourniquet time and the orders between the two groups. Group 1 had significantly less subcutaneous bleeding than did group II on the 3rd and 6th days after the operations (p=0.001). CONCLUSION: There was a significant difference of the amount of subcutaneous bleeding amount according to the tourniquet pressure. We were able to decrease the post-operative amount of subcutaneous bleeding after total knee replacement by lowering the tourniquet pressure to 250 mm Hg.

The Analysis of Risk Factors in No Thumb Test in Total Knee Arthroplasty

BACKGROUND: We would like to analyze the risk factors of no thumb test among knee alignment tests during total knee arthroplasty surgery. METHODS: The 156 cases of total knee arthroplasty by an operator from October 2009 to April 2010 were analyzed according to preoperative indicators including body weight, height, degree of varus deformity, and patella subluxation and surgical indicators such as pre-osteotomy patella thickness, degree of patella degeneration, no thumb test which was evaluated after medial prepatella incision and before bone resection (1st test), no thumb test which was evaluated with corrective valgus stress (2nd test, J test), and the kind of prosthesis. We comparatively analyzed indicators affecting no thumb test (3rd test). RESULTS: There was no relation between age, sex, and body weight and no thumb test (3rd test). Patellar sulcus angle (p = 0.795), patellar congruence angle (p = 0.276) and preoperative mechanical axis showed no relationship. The 1st no thumb test (p = 0.007) and 2nd test (p = 0.002) showed significant relation with the 3rd no thumb test. Among surgical indicators, pre-osteotomy patella thickness (p = 0.275) and degeneration of patella (p = 0.320) were not relevant but post-osteotomy patellar thickness (p = 0.002) was relevant to no thumb test (3rd test). According to prosthesis, there was no significance with Nexgen (p = 0.575). However, there was significant correlation between Scorpio (p = 0.011), Vanguard (p = 0.049) and no thumb test (3rd test). Especially, Scorpio had a tendency to dislocate the patella, but Vanguard to stabilize the patella. CONCLUSIONS: No thumb test (3rd test) is correlated positively with 1st test, 2nd test, and post-osteotomy patella thickness. Therefore, the more patella osteotomy and the prosthesis with high affinity to patellofemoral alignment would be required for correct patella alignment.

Correlation Between Degree of Adolescent Thoracic Kyphosis and Low Back Pain: Using 3-Dimension Whole Body Analyzer (BodyCheck 3D BM101R) / 대한정형외과연구학회지

PURPOSE: This study was designed to evaluate the correlation between the degree of kyphosis among adolescent spine deformities and low back pain in male adolescent using the 3-Dimensional Whole Body Scanner as screening tool for kyphosis. MATERIALS AND METHODS: The 3-Dimensional Whole Body Scanner was applied to 220 first-year, second-year and third-year high school male students in Seoul, in addition to administering a survey regarding the presence of back pain. From the gathered data, we calculated the A/B index to objectively analyze the degree of spinal deformity, more specifically, spinal kyphosis. We were able to obtain the A/B index of a total of 210 students except unmeasurable 10 students and analyzed the relationship between the degree of kyphosis and low back pain using logistic regression. RESULTS: 1. The average age, height, body weight and body mass index were 16.7+/-0.9 years old, 173.1+/-5.0 cm, 65.6+/-10.2 kg, 21.8+/-3.2 kg/m2. The average of A/B index is 11.3+/-3.65%. The maximum and minimum were 2% and 36%. A/B index data showed normal distribution. 2. Low Back Pain did not correlate with age, height, or weight, but with the degree of thoracic spine kyphosis. As the degree of thoracic spine kyphosis increased by 1%, 5%, and 10%, the incidence of low back pain increased by 1.2 times, 2.5(falling dots1.25) times and 6.2(falling dots1.210) times respectively. CONCLUSION: We concluded that the degree of kyphosis has a significant correlation to low back pain in male adolescences.

Treatment for Periprosthetic Supracondylar Femur Fractures Following Total Knee Arthroplasty -Comparative Study of Retrograde Intramedullary Nailing and Locking Compression Plate Fixation-

PURPOSE: The purpose of this research is to compare the clinical and radiological results of retrograde intramedullary nailing and locking compression plate fixation. Both of these are surgical procedures for the treatment of periprosthetic supracondylar femur fractures that occur subsequent to total knee arthroplasty. MATERIALS AND METHODS: The subject population consisted of 23 cases: there were 10 cases that underwent retrograde intramedullary nailing fixation (group 1) and 13 cases that underwent use of a locking compression plate (group 2), and in both groups supracondylar femur fracture subsequent to total knee replacement occurred during the period between January 2004 and December 2008. The range of joint motion, the Hospital for Special Surgery (HSS) knee score, the tibio-femoral angle and the time to achieve bone union in each group were comparatively analyzed. RESULTS: The mean range of the knee joint motion decreased from 124.5degrees to 116.2degrees in group 1, and from 118.2degrees to 110.1degrees in group 2. The mean HSS knee score declined from 84.4 points to 75.8 points in group 1, and from 82.3 points to 79.0 points in group 2. The mean tibio-femoral angle changed from 6.3degrees eversion to 5.8degrees in group 1, and from 6.1degrees to 7.2degrees in group 2. The mean time to achieving bone union was 2.7 months in group 1 and 3 months in group 2. CONCLUSION: Both retrograde intramedullary nailing and locking compression plate fixation, as surgical procedures for the treatment of periprosthetic supracondylar femur fractures that occur subsequent to total knee replacement, allow solid fixation and early resumption of joint movement without any statistically significant differences between the two procedures. So, both procedures appear to be good methods of treatment.

The 'beta-wire Technique' for the Fixation of Ulnar Styloid Process Fracture: Surgical Technique

For the fixation of ulnar styloid process fracture, we want to introduce the 'beta-wire technique', which is easy to learn and practice and thought to give a compressive force to the fracture site.

Causes and Treatments of the Early Failure after Unicompartmental Knee Arthroplasty

PURPOSE: We wanted to evaluate the causes, treatments and preventive measures for early failure of unicompartmental knee arthroplasty (UKA) by performing an analysis of the cases. MATERIALS AND METHODS: We retrospectively analyzed 687 cases of UKA that had been performed from January 2002 to December 2006. There are 622 cases of the meniscal bearing type, 31 cases of the tracked bearing type and 34 cases of the fixed bearing type. All of the cases were performed by minimally invasive surgery. RESULTS: Early failures after UKA were seen in 36 cases, and these failures occurred from 4 months postoperatively to 5 years 7 months postoperatively. There were 20 mobile bearing dislocations, 18 femoral or tibial component loosenings, 4 infections, 1 medial tibial condylar fracture and 1 case of pain of unknown origin. The most common cause of the failed cases of the meniscal bearing type was bearing dislocation. All of the failed cases of the tracked and fixed types were from loosening of the component. Simple dislocations of bearing were treated by bearing change. All of the other cases were treated with revision TKA or UKA. CONCLUSION: Selection of an appropriate prosthesis and accurate surgical technique are needed to improve the clinical results and reduce failures. Open bearing change can be done for the cases of simple bearing dislocation, and revision TKA is needed if this is accompanied by other complications.

Efficacy of High Intensity Laser Therapy in the Mild Osteoarthritis of the Knee: A Randomized Double-blind Controlled Trial / 대한정형외과연구학회지

PURPOSE: The purpose of this study is to know the effect of high intensive laser therapy in patients with early stage of osteoarthritis of knee. MATERIALS AND METHODS: This study was a randomized, double blind controlled trial. 28 patients who had grade II osteoarthritis of Kellgren classification and knee pain were randomly divided into two groups. Patients underwent treatment 30 times, 5 times per week. the clinical evaluation was done by the pain, stiffness and functional score of the knee by the knee society clinical rating system, and the intensity of pain was measured also by a VAS (visual analogue scale), before and after the 1st sessions, Before and after the 2nd sessions and at 6 month after the 1st treatment. We checked hs-CRP and HA which was regarded as indexes of osteoarthritis activitiy. RESULTS: As a clinical result of high intensive laser therapy, VAS, pain and functional score were statistically more improved than those of before therapy, except stiffness (P<0.05). The results of the hs-CRP and HA which were not significantly different from those of before therapy. In the placebo group, all variables showed no difference. CONCLUSION: We concluded that Nd-YAG high intensive laser therapy in early stage of patient with osteoarthritis of knee would be helpful as noninvasive and conservative treatment for improvement clinical progress.

Injury of Posterior Ligament Complex with Cervical Spine Fracture / 대한척추외과학회지

OBJECTIVE: To define the clinical and radiological characteristics of the patients with injury of the posterior ligament complex of the cervical spine using MR imaging. MATERIALS AND METHODS: Forty patients with acute cervical spine fracture who underwent surgery were examined with MR imaging and plain radiography. Twenty-five patients underwent posterior fusion. The MR findings were correlated with surgical findings, clinical findings, and plain radiographs. RESULTS: Posterior ligament complex injury was detected in 75% (n=30) of all patients. Of the 20 patients with distractive-flexion injury, 90%(n=18) had posterior ligament complex injury (p<0.05). Of the 15 patients with compressive-flexion injury, 73% (n=11) had ligament injury. Of the 4 patients with vertical compression injury, 1 patient (25%) showed ligament injury. One patient with distractive-extension injury did not show ligament injury. Of the 23 patients with complete spinal cord injury, 96% (n=22) showed ligament tear (p<0.05). Of the 17 patients without complete cord injury (15 incomplete injury, 2 no cord injury), 47% (n=8) had ligament injury. Surgical findings were well correlated with MR imaging in patients who underwent posterior surgery (p<0.05). CONCLUSIONS: Injury of the posterior ligament complex in patients with cervical spine fracture was most common in patients with distractive-flexion injury and was more frequent with complete cord injury. MR imaging could reliably reveal such injuries.

Trigger Thumb in Children / 대한정형외과학회잡지

PURPOSE: We tried to define the etiology of the trigger thumb in children, to know the main symptom of the trigger thumb in children and to conclude the prophet age to operate without residual symptoms nor complications. MATERIALS AND METHODS: 1) 50 Children, 60 thumbs operated in our hospital (A1 pulley release after the age of 2) were included in this study. 2) In 7407 newborn babies born in our hospital, screening test were performed for detection of trigger thumb in nursery and also follow-up (180 days or more) for detection of trigger thumb was performed. RESULTS: 1) In 50 children underwent operation, only two (4%) had the deformity at the day of birth. All the babies (100%) had flexion contractures of the interphalangeal joint of the thumb. The nodule was found in 48 (80%) of 60 thumbs. The triggering, however, was found in only 16 thumbs (27%) . The patients underwent operation after the age of 4 (11 patients, 22%) had no complication nor residual symptom. 2) In the screening of 7407 newborn babies, nobody had flexion contractures of the thumb at the day of birth. CONCLUSIONS: 1) The main symptom of the trigger thumb in children was "flexion contracture", not "triggering". 2) The children operated after the age of 3 or 4 is expected to get good result.3) The trigger thumb in children is seemed to be "acquired" or "developmental" rather than "congenital".