Cement Fixation Technique for a Femoral Stem

Cemented total hip arthroplasty was first introduced by Sir John Charnley in 1961 and it has become one of the principal fixation techniques for fixation of an implant. The surgical technique has since been modified and this has resulted in improved longevity and reliability. The clinical success of the cemented technique has varied in literature, and this has been reported as 30~40% failure to 2% failure for 14 years of follow up using the 2nd generation cement technique. Currently, the successful clinical results can be contributed to the better developed design of the femoral stem and the advancement of the 3rd and 4th generation cement fixation techniques. As society gains more elderly people, for the older patients who have osteoporosis, a wide and thin femur would be the best indication for cement fixation in order to achieve early stability and better clinical results. It is imperative to learn and practice performing the exact cement fixation technique to achieve the best clinical results.

Varus Positined Femoral Stem in Cementless Total Hip Arthroplasty / 대한정형외과학회잡지

PURPOSE: This study examined the effect of a varus positioned femoral stem after cementless proximal fitting total hip arthroplasty. MATERIALS AND METHODS: A total of 144 hips in 136 patients who underwent cementless total hip arthroplasty, were followed-up. Twenty-one varus positioned hips were compared with 123 neutral positioned hips. The clinical results were analyzed according to the level of thigh pain and the Harris Hip score. The radiological outcome was assessed according to osteolysis, loosening and stem failure. RESULTS: In the varus positioned hips, thigh pain was present in 1 hip, and the average Harris Hip Score was 96 points. None of the implants showed radiological evidence of loosening or impending failure. Localized osteolysis was identified in 1 hip, non-progressive radiolucencies in 2 hips, and cortical hypertrophy in 1 hip. In the neutral positioned hips, thigh pain was present in 6 hips, and the average Harris Hip Score was 97 points. Localized osteolysis was identified in 8 hips, non-progressive radiolucencies in 7 hips, cortical hypertrophy in 9 hips. CONCLUSION: Patients with varus alignment of the stem did not present poorer clinical outcomes than those with neutral alignment of the stem.

Intrathoracic Migration of K-wire after Fixation of Proximal Huemrus Fracture: Case Report

We report an unusual case of Kirschner wire migration from the proximal humerus into the thoracic cavity and diaphragm which induced pneumothorax and hemoperitoneum. An 81-year-old woman admitted to the emergency room due to sudden onset of dyspnea. X-rays showed pneumothorax and old proximal humerus fracture fixed with rush pins and K-wires. One of K-wires was seen on the diaphragm level at posterior gutter of chest wall. Through the abdomen, K-wire was removed from the diaphragm and a chest tube was inserted. The potential for K-wires to migrate must be recognized, and frequent postoperative radiographic studies have to be performed for the early detection of loosening and migration. It appears that if K-wires are used for fixation of proximal humerus, the lateral ends must be bent to prevent medial migration, and when the desired therapeutic goals have been achieved, these pins have to be susbsequently removed as soon as possible.

Double-Chevron Subtrochanteric Osteotomy Combined with Total Hip Replacement Arthroplasty for Treatment of Neglected Highly Dislocated Hip in Adults / 대한정형외과학회잡지

PURPOSE: This study evaluated total hip replacement arthroplasty (THRA) combined with a double-chevron subtrochanteric osteotomy for the treatment of neglected highly dislocated hips in adults. MATERIALS AND METHODS: Six cases treated with THRA combined with a double-chevron subtrochanteric osteotomy under the diagnosis of a neglected highly dislocated hip (Crowe classification IV) from April 1997 to October 2001 were followed up for between 21 months and 75 months. Harris hip scores, leg length discrepancy pre and postoperatively, osteotomy site union and implant loosening were chekced. RESULTS: The average Harris hip score increased from 61 points preoperatively to 94 points postoperatively. The average leg length discrepancy was decreased from 6 cm preoperatively to 1.8 cm postoperatively. Bone union of the osteotomy site was obtained at 4 months after surgery. The radiographs showed no acetabular and femoral loosening sign at the latest follow up. CONCLUSION: According to the clinical and radiological assessments, THRA combined with doublechevron subtrochanteric osteotomy gave satisfactory results in adults with a neglected highly dislocated hip in adults on a midterm follow up.

The Role of Extracellular Superoxide Dismutase (EC-SOD) in Skeletal Muscle Ischemia-reperfusion Injury / 대한정형외과학회잡지

PURPOSE: This study investigated the role of extracellular superoxide dismutase (EC-SOD), which is a major extracellular antioxidant enzyme in skeletal muscle ischemia and reperfusion (I/R) injury. MATERIALS AND METHODS: The pedicled cremaster muscle flaps from homozygous EC-SOD knockout (EC-SOD-/-), heterozygous CuZn-SOD knockout (CuZn-SOD+/-) and wild-type (WT) mice were subjected to 4.5 hour ischemia followed by 90 min reperfusion. The pedicled cremaster muscle flaps were examined by functional analysis during the reperfusion. The mRNA and protein expressions of each SOD after I/R were evaluated using quantitative real-time PCR and western blot. RESULTS: The results showed that the EC-SOD-/- mice had a more profound I/R injury than the CuZn- SOD+/- or WT mice. In particular, there was a delayed and incomplete recovery of the arterial diameter and blood flow during reperfusion and as well as there being more severe inflammation. After 90 min reperfusion, the EC-SOD mRNA levels increased more in the CuZn-SOD+/- mice than in the WT mice. However, the CuZn-SOD and Mn-SOD mRNA levels decreased similarly in all 3 groups. The CuZn-SOD protein levels decreased in all groups. The EC-SOD protein levels decreased in the CuZn-SOD+/- and WT mice, but the Mn-SOD protein levels were unchanged or slightly increased in all groups. The histological results showed diffuse edema and inflammatory cell infiltration around the muscle fibers and these changes were more severe in the EC-SOD-/- mice. CONCLUSION: EC-SOD plays an important role in protecting the skeletal muscle from I/R injury caused by the excessive generation of reactive oxygen species.

The Effect of Nitric Oxide Donor, SNAC on Motor Functional Recovery of Reperfused Peripheral Nerve / 대한정형외과학회잡지

PURPOSE: To investigate the effects of nitric oxide (NO) donor, S-nitroso-N-acetylcysteine (SNAC) on the motor functional recovery of a reperfused rat sciatic nerve. MATERIALS AND METHODS: Seventy-eight rats were divided into the following 3 groups: SNAC, methylprednisolone (MP), and phosphate buffered saline (PBS)-treated groups. A 1 cm segment of the sciatic nerve underwent 2 hours of ischemia followed by 90 minutes of reperfusion. The results were evaluated using a walking track test, muscle contractile test and an examination of the muscle weight and histology at various reperfusion periods. RESULTS: There was a significant improvement in the sciatic functional index (SFI) and contractile force of the SNAC-treated group compared with the MP and PBS groups. The SNAC group showed earlier improvement in the SFI measurement between days 7-28. The contractile force and muscle weight of the extensor digitorum longus muscle began to be restored earlier in the SNAC group after day 11, while the others showed progressive atrophy until day 21. The histology examination revealed less severe degeneration and earlier regeneration of axons in the SNAC-treated rats than the other groups. CONCLUSION: The supplementation of NO is effective in promoting the motor functional recovery of a reperfused peripheral nerve and has the potential to replace or augment steroids as a therapeutic agent in the treatment of nervous system ischemia/reperfusion injuries.

Rapid Neurorrhaphy with Titanium Clips / 대한정형외과학회잡지

PURPOSE: To evaluate the usefulness of titanium clips applied for the repair of transected peripheral nerve. MATERIALS AND METHODS: The results of neurorrhaphy using a titanium clip (VCS) was compared with the conventional technique of neurorrhaphy with a nylon suture. In fifteen New Zealand white rabbits, transected sciatic nerves were repaired with VCS clips on one side and interrupted 9-0 nylon suture on the other. RESULTS: The time required for the neurorrhaphy was 14.9+/-3.55 minutes for suture closure and 8.7+/-2.6 minutes for clip closure (p<0.01). Electromyographic studies were performed at 1, 2 and 3 months after the initial operations. No significant differences in the amplitudes of the complex motor action potentials were noted between the groups. In the microscopic study, no significant differences in the numbers and the extents of myelinization of the regenerated axons of both methods of nerorrhaphy were evident. CONCLUSION: The titanium clip that was initially designed for microvascular anastomosis can be applied successfully for the microscopic neurorrhaphy of the peripheral nerve. Microscopic neurorrhaphy with titanium clips can be performed more rapidly than conventional suture repair.

Microvascular Anastomosis of Rabbit's Jugular Vein with Titanium Clip / 대한정형외과학회잡지

PURPOSE: We compared the results of micovascular anastomoses using a titanium clip and a conventional suture method to determine the possibility of clinical applying titanium clips for the anastomosis of small vessels. MATERIALS AND METHODS: In 15 New Zealand white rabbits, jugular veins on both sides were cross-sectioned. One side was repaired with a titanium clip and the other with 10-0 nylon sutures. Macroscopic and microscopic results of anastomoses were evaluated. RESULTS: All of the anastomsed vessels were patent at postoperative 1 day, 1 week and 1, 2 and 3 months. The time required for vessel repair was 16.0 minutes for suture repair and 8.9 minutes for clips. Microscopic evaluation revealed that the titanium clips didn't penetrate the intima of the vein. Foreign body reaction was less at the clipped anastomoses sites than at those with suture repair. CONCLUSION: Microvascular anastomosis can be performed more rapidly with titanium clips than conventional suture repair in operations of major limb replantation or free flap surgery where ischemic time is critical. This device minimizes intimal injury and foreign body reaction, and could reduce the failure rate after microvascular anastomosis.

The Study on the Preventive Method of the Middle Ear Barotrauma Caused by Hyperbaric Oxygen Therapy / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Middle ear barotrauma is a damage of the ear resulting from the pressure difference between the middle ear and the atmospheric environment. We investigated the effects of chewing gum and administering the systemic decongestant in hyperbaric oxygen therapy. MATERIALS AND METHOD: We investigated the cases of the middle ear barotrauma which came from hyperbaric oxygen therapy for finger replantation. We studied 81 patients without E-tube dysfunction. They were divided into three groups: the non-treated patients, the patients chewing gums and receiving high-pressure treatment, and the patients receiving the systemic decongestant. We investigated the patients for symptoms, otoscopic findings, tympanometry, and PTA. Otoscopic findings were classified by modified Teed classification. RESULTS: In the first group, 36 of 60 (60%) ears had otologic symptoms, 37 of 60 (62%) ears were above the grade 1, 31 of 60 (52%) ears were B or C type in tympanometry and 20 of 60 (33%) ears were above 20dB in AB gap (air-bone gap). In the second group, 23 of 60 (38%) ears had the otologic symptom, 26 of 60 (43%) ears were above the grade 1, 19 of 60 (32%) ears were the B or C type and 10 of 60 (17%) ears were above 20dB in AB gap. In the third group, 18 of 42 (43%) ears had the otologic symptoms, 19 of 42 (45%) ears were above the grade 1, 15 of 42 (36%) ears were the B or C type and 7 of 42 (17%) ears were above 20dB in the AB gap. CONCLUSION: The second group was better than the first group with regard to otologic symptom, otoscopic findings, tympanometry, PTA, and showed statistical significance. On the other hand, the third group was effective but did not show statistical significance.

Micromotion of Cementless Straight and Curved Femoral Stems by Three Dimensional FEM analysis / 대한정형외과학회잡지

PURPOSE: The purpose of this study was to analyze the relative micromotions between the straight and the curved stems during the immediate postoperative stage of noncemented total hip replacement which load simulating the single leg stance and stair climbing. MATERIALS AND METHODS: The authors developed 3-dimensional numerical finite element models implanted with the straight stem, which was composed of a total of 1,170 elements of 8 nodes, and which had a curved stem composed of a total of 885 elements of 8 nodes, and then analyzed the relative micromotions of the straight and curved stems. RESULTS: In the single leg stance, the curved stem was more stable especially in terms of its rotational stability. Rotational displacement accounted for over 90% of the total micromotion in both types of stem and this was highest for the proximal medial portion of the stem, but markedly less distally. Stair climbing produced more micromotion than the single leg stance regardless of the stem configuration. CONCLUSION: It is recommended that surgeons do not allow patient weight bearing until bony ingrowth has been achieved. In the future more attention should be placed upon increasing the initial rotational stability of the two types of femoral stem to prevent loosening by excessive micromotion.

Biomechanical Analysis of Proximal Fitting-Distal Filling Stem and Proximal Fitting- Distal Tapered Stem in Cementless Hip Prosthesis: A 3 Dimensional Finite Element Study / 대한정형외과학회잡지

PURPOSE: This study was undertaken to compare the initial micromotion and stress shielding of a "fit and fill" stem to a "proximal fitting and distal tapered" stem in the early postoperative period using the load simulating single leg stance and stair climbing. MATERIALS AND METHODS: Using the data from 3-D human CT scan, authors developed two types of 3-dimensional finite element total hip replacement model of proximal femur, which were inserted with a "fit and fill" stem and a "proximal fitting and distal tapered" stem. The constructions of stems were based on the OmnifitTM stem (about 13,000 element & 20,000 nodes). We compared micromotion, maximal principal stress and strain energy of each stems. RESULTS: The results indicate that micromotion in a fit and fill stem were slightly lower than that of a tapered stem, especially in stair climbing over that in the single leg stance. The maximum principal stress on the cortex of femur was slightly higher in a tapered stem in the case of single leg stance, and 2 times higher in the case of stair climbing. Strain energy also was much higher in a tapered stem in both single leg stance and stair climbing gait. CONCLUSION: These findings indicate that a tapered stem design could provide more favorable biomechanical benefits rather than a fit & fill stem after cementless total hip replacement.

Non-union of Scaphoid Fracture: Comparison according to the Method of Operation / 대한정형외과학회잡지

PURPOSE: To evaluate the operative methods which can induce an early uinon and better functional outcome in the non-union of scaphoid fracture. MATERIALS AND METHODS: We evaluated 16 patients (16 cases) who had taken autogenous iliac bone graft and internal fixation with compression screws or K-wires for the treatment of scaphoid fracture non-union. The average follow-up period was 21.1 months. Anteroposterior, lateral and scaphoid views were taken at last follow-up for the purpose of evaluating radiological results. The ranges of wrist motion and grip strength were measured to evaluate functional results, and the patient's subjective responses were also evaluated. RESULTS: Radiological unions were obtained in 15 cases (93.8%) with the average time to union at 3.2 months (2~7 months) . Radio-ulnar deviation arcs and grip strength were better in the cases fixated with compression screws than K-wires. Twelve patients (75%) showed satisfactory subjective results at the time of last follow up. CONCLUSION: The iliac bone graft is a good treatment method for scaphoid fracture non-union. We think that the compression screw, which has better stability, is a more profitable fixation device for improved functional recovery.

Fusion and Clinical Results of Instrumented Posterolateral Fusion with Autograft or Xenograft Bone / 대한정형외과학회잡지

Recently, xenograft is being increasingly used in spinal fusion to reduce complications such as pain or bleeding following autograft bone grafting. The purpose of this study was to compare the fusion rate and clinical results between autograft and xenograft in 69 patients who had posterolateral lumbar fusion with instrumentation from March 1989 to April 1997. The xenograft was mixed with autogenous bone chips obtained from decompresion. Fusion and clinical results were evaluated with Furguson's method and Modified Smiley-Webster' scale, respectively. The mean follow-up time was 26 months with a minimum of 12 months and a maximum of 41 months. The results are as follows: fusion rates of autograft were 64.6% in Furguson grade A, 25.8% in grade B, 6.4% in grade C and 3.2% in grade D. Xenograft was 15.7% in grade A, 47.6% in grade B, 23.6% in grade C and 13.1% in grade D. Clinical results of autograft were excellent in 29.0%, good in 61.3%, fair in 6.5% and poor in 3,2%. Xenograft was excellent in 23.8%, good in 57,8%, fair in 15.8% and poor in 2.6%. Autograft showed a higher fusion rate of 90.4% than xenograft of 63.3% in grade A and B (P=0.012). Clinical results were not different between autograft and xenograft groups (P=0.494). However, the xenograft group showed lower fusion rate than the autograft group. The results indicated that xenograft is less useful for posteolateral fusion of the lumbar spine.

Biomechanical analysis of the Effect of Debondign of Cement - Femoral Stem Interface to the Cement - Bone Interface - three - dimensional non - linear finite element analysis - / 대한정형외과학회잡지

Debonding of cement-femoral stem interface has been suggested as a initial focus of loosening mechanism in many previous studies of cemented total hip replacement. The purpose of this study was to investigate the effect of debonding of cement-femoral stem interface to the cement-bone inter- face by using three-dimensional non-linear finite element analysis. Three cases of partial debonded, full debonded, and full bonded cement-bone interface were modelled with partial bonding of distal 70mm from the tip of femoral stem. Each situation was studied under loading simulating one-leg stanced gait of 68kg patient. The results showed that under partial and full debonded cement-stem interface conditions the peak von Mises stress (3.1 MPa) were observed at the cement of cement-bone interface just under the calcar of proximal medial of femur, and sudden high peak stresses (3.5 MPa) were developed at the distal tip of femoral stem at the lateral bone-cement interface in all 3 cases of bonding. The stresses were transfered very little to the cement of upper lateral bone-cement interface in partial and full debonded cases. Once partial or full debonded cement-femoral stem interface occured, 3 times higher stress concentration were developed on the cement of proximal medial cement-bone interface than full bonded interface, and these could cause loosening of cemented total hip replacement. Clinically, preservation of more rigid cement-femoral stem interface may be important factor to prevent loosening of femoral stem.

Orotracheal Intubation with Magnet / 대한마취과학회지

BACKGROUND: Every practitioner, however skilled, will encounter patients who are unexpectedly difficult to intubation. The incidence of difficult laryngoscopy appears to be approximately 0.5% to 2%. So many methods are used to intubate the trachea, but endotraheal intubation by them is not always possible. The purpose of the this study is to evaluate the effectiveness of magnet on the endotracheal intubation. METHODS: Twenty patients(aged 30 to 59yr, ASA physical status 1) required general anesthesia with an endotracheal tube. Anesthesia was induced with thiopental sodium and succinylcholine, ventilation was controlled with 100% O2. The tip of the epiglottis was exposed wtih a No.3 MacIntosh laryngoscope. A catheter with ferrous stylet was placed behind epiglottis close to tracheal lumen and a magnet was placed over the cricoid cartilage allowing the stylet to be pulled. Endotraheal tube was guided into the trachea over the stylet. The time to intubation, the blood pressure and heart rate of pre- and postintubation, and the difficulty of intubation were recorded and the complications of the endotracheal intubation such as bronchial spasm, oral and tracheal mucosal trauma, and sore throat, were observed. RESULTS: The mean time to intubation was 31.2+/- 8(18 to 50)sec. There were statistically signigicant increase in blood pressure and heart rates following intubation. The incidence of excellent and good intubating condition were 14 and 6 respectively. Seventeen and three intubations were successful on the 1st and 2nd attempts respectively. There were no differences in incidence of complications of endotracheal intubation compared to other reports. CONCLUSIONS: Though magnet guided technique has some limitations to use in case of difficult laryngoscopy, it can be used with merits such as simplicity and cheapness when other methods are not available.

Femoral Bone Resorption after Cementless Total Hip Arthroplasty / 대한정형외과학회잡지

Bone resorption around femoral stem as an effect of stress shielding and a subsequent adaptive remodeling process is a disturbing phenomenon. The purpose of this study is to analysis the degree, the location and the time of appearance of femoral bone resorption after cementless total hip replacement and to evaluate the factors affecting the degree, the location and the time of appearance of bone resorption. The authors analysed total 48 cases of standard radiographies which underwent operation between September, 1983 to May, 1994 at Korea University, Guro Hospital and the mean duration of follow up was average 16 months(range 7 months to 5 years). The results were as follows; 1. Bone resorption could be observed mostly in proximal portion of femur and the extent was limited to the first and the second degree according to Engh’s classification in most cases. 2. The degree of bone resorption was significantly correlated with the diameter of femoral stem. 3. The time of appearance of bone resorption after THR was not statistically correlated with the diameter of femoral stem. 4. The degree of bone resorption was not related with sex, age, preoperative diagnosis, type of femoral stem and degree of press-fitting. In conclusion bone resorption as an adaptive bone remodeling process after cementless total hip replacement could be observed in the proximal femur, and the factors affecting the degree of bone resorption were closely related with the size of femoral stem, but not related with sex, preoperative diagnosis, press-fitting and type of femoral stem. From the mechanical point of view, we could conclude that the bending stiffness of a prosthesis was the most important factor affecting the degree of bone resorption.

Surgical treatment of thoracolumbar fractures with transpedicular screws / 대한정형외과학회잡지

No abstract available.

The treatment and clinical analysis of lateral malleolar fracture of the ankle with one or two cortical lag screws / 대한정형외과학회잡지

No abstract available.

A Comparison between Renal Ultrasonogram and Intravenous Pyelogram as a followup Study in Spinal Cord Injury Patients / 대한비뇨기과학회지

During the lest 7 years 21 children with vesicoureteral reflux and neurogenic bladder dysfunction and 46 children with primary vesicoureteral reflux were followed. At the time of initial presentation, the mean age of the former group was 5.5 years and the letter group, 2.8 years. The grade of reflux and the nephropathy were more severe in the children with neuropathic bladder than in the children with primary vesicoureteral reflux But in the same reflux grade, there was no statistical difference in the nephropathy between the two groups. The children with vesicoureteral reflux and neuropathic bladder were managed with drug therapy, intermittent catheterization, urinary diversion and ureteral reimplantation. Radiological followup revealed that resolution or improvement of reflux occurred in 36 per cent of renal units managed by intermittent catheterization and 100 per cent in which the ureters were reimplanted. As in the non-neurogenic bladder successful management of reflux and prevention of upper tract deterioration can be achieved by conservative management as well as by ureteroneocystostomy.

Torsion of the Cryptorchid Testis: Report of Two Cases / 대한비뇨기과학회지

Because of its usually abnormal mesorchial attachments the undescended testis is more prone to undergo torsion than normally-sited organ, but the incidence of this complication appears to have lessened in recent years. We present two cases with torsion of the unilateral cryptorchid testis and a review of the literature. Two cryptorchids complained of the painful mass on the inguinal area. Exploration revealed testicular torsion and orchiectomy was done.