Risk Factors of Cut-Out in Treatment of Femoral Intertrochanteric Fractures by Proximal Femur Nail / 대한정형외과학회잡지

PURPOSE: The purpose of this study is to evaluate the risk factors for the occurrence of cut-out of proximal femoral nail by a lag screw as the treatment for intertrochanteric fractures. MATERIALS AND METHODS: A total of 151 patients (76 males and 75 females; mean age, 73.7±12.1 years), who were diagnosed with intertrochanteric fracture at Gyeongsang National University Hospital between January 2011 and March 2016, with a follow-up of at least for 6 months were included in this retrospective study. Various risk factors, such as demographic data, osteoporosis, collodiaphyseal angle (CDA) (≤130° or >130°), tip-apex distance (TAD) (≤25 mm or >25 mm), and the position of lag screw in the femur head (quadrant) related to the occurrence of cut-out were taken into consideration. The strength of association for each factor was determined through the calculation of the odds ratio (OR), within the 95% confidence interval (CI). First, we performed univariate logistic regression analyses for all variables; then, we performed a multivariate logistic regression analysis, using only the significant variables that had resulted from the univariate analysis. RESULTS: Among the 151 cases, the occurrence of cut-out was observed in 14 cases (9.3%). In a univariate analysis, the fracture patterns based on the AO/OTA classification (p=0.045), CDA (p<0.001) and the position of lag screw in the femur head (quadrant) (p=0.001) showed a significant association with the occurrence of the cut-out. However, TAD was not significantly associated with the cut-out (p=0.886). Various factors, which were significant in univariate analyses, were included in multivariate analyses. In multivariate analyses, CDA (OR, 12.291; 95% CI, 2.559-59.034; p=0.002), and quadrant (OR, 7.194; 95% CI, 1.712-30.303; p=0.007) were significantly associated with the cut-out. CONCLUSION: Valgus reduction and proper position of lag screw were critical for the prevention of occurrence of cut-out when treating intertrochanteric fracture using proximal femur nail.

Conservative Treatment of Pyogenic Spondylitis in the Elderly

STUDY DESIGN: Retrospective study. OBJECTIVES: To analyze the outcomes of conservative management in elderly patients over 65 years of age who were diagnosed with pyogenic spondylitis. SUMMARY OF LITERATURE REVIEW: The surgical treatment of pyogenic spondylitis can lead to complications in elderly patients in a poor general condition or with underlying diseases. MATERIALS AND METHODS: We performed a retrospective review of 32 patients who were diagnosed with pyogenic spondylitis and had a minimum of 12 months of follow-up. Age, sex, comorbidities, clinical symptoms, and the involved segments were analyzed retrospectively. The diagnosis was assessed using clinical, laboratory, and radiologic findings. Antibiotic therapy was either specific (if positive culture results were found) or broad-spectrum cephalosporin (when the pathogenic agent was not isolated). Outcomes were assessed using residual pain and neurologic deficits. RESULTS: The mean onset time was 23.5 days (range, 3-90 days). The mean period of intravenous antibiotic therapy was 36.3 days (range, 10-90 days). All cases underwent conservative management, and 4 patients with progressive neurologic deficits due to epidural abscess underwent posterior laminectomy and abscess drainage. In all cases, the infection was successfully treated, although 12 cases reported residual lower back pain and 2 continued to exhibit minor neurologic deficits. CONCLUSIONS: In elderly patients with pyogenic spondylitis, satisfactory results were obtained with conservative management using antibiotics and orthosis after an early diagnosis, unless progressive neurologic symptom instability or spine deformities were noted.

Epidural Lymphoma Mimicking Hematoma: A Case Report

STUDY DESIGN: Case report. OBJECTIVES: To present a rare case of a spinal epidural lymphoma mimicking a hematoma. SUMMARY OF LITERATURE REVIEW: The incidence of extranodal invasion of lymphoma is very low, and spinal compression as a clinical symptom rarely occurs in extranodal lymphoma. MATERIALS AND METHODS: A 37-year-old woman who complained of neck pain that had lasted for the past 3 months with no underlying disease visited the hospital and was treated conservatively with medication and physical therapy. Even though the patient was given an epidural injection 1 month prior to visiting our hospital, the pain lingered and the cervical myelopathy became aggravated, so the patient was initially diagnosed with epidural hematoma. This predisposed the patient to treatment strategies such as laminectomy and fusion, but the patient was ultimately diagnosed with non-Hodgkin lymphoma. RESULTS: The patient underwent a laminectomy with excision of the lesion and fusion. The patient was diagnosed with non-Hodgkin lymphoma as a result of this, and the patient's radicular pain and numbness improved immediately following surgery, except for mild weakness in both hands. CONCLUSIONS: Although spinal epidural lymphoma is similar to hematoma, and is a very rare disease, surgeons should take it into consideration in the differential diagnosis of patients with a spinal epidural lesion.

Nucleoplasty: Percutaneous Plasma Disc Decompression for the Treatment of Lumbar Disc Herniation

STUDY DESIGN: A review of the literature regarding nucleoplasty. OBJECTIVES: This aim of this article is to provide current information on nucleoplasty as a therapeutic intervention for herniated disc or discogenic back pain in degenerative disc disease. SUMMARY OF LITERATURE REVIEW: Nucleoplasty as a therapeutic intervention for discogenic pain is performed with increasing frequency, and has been reported to involve few complications and to have satisfactory clinical results. MATERIALS AND METHODS: Review of the literature. RESULTS: In nucleoplasty, the intervertebral disc is approached percutaneously. In this paradigm, a bipolar high frequency device in combination with ablation and coagulation is used to create a channel in the intervertebral disc in order to reduce intervertebral disc volume and to decrease intervertebral pressure and inflammatory markers. Standard indications for nucleoplasty have not been established, but it has been reported that the procedure had excellent outcomes regardless of the presence of radiculopathy or the results of discography. Many studies have reported their outcomes using various categories, because the procedure is comparatively new. Concomitantly, long-term follow-up studies remain to be performed, and each study reported a different follow-up period. CONCLUSIONS: Nucleoplasty has been found to show an excellent prognosis for discogenic back pain and a low incidence of complications. Moreover, since it is a minimally invasive procedure, it offers improved possibilities for return to daily life and work. If degenerative changes have not progressed to a great extent or the intervertebral level remains intact, nucleoplasty may be considered prior to surgery. Due to the lack of reports on the subject, prospective analyses in the future are required.

Risk Factors of Cervical Spondylosis in Workers Requiring Neck Flexion and Extension Actions in Farming and Fishing Communities / 대한정형외과학회잡지

PURPOSE: The purpose of this study is to determine the relationship between the repetitive flexion or extension posture on the cervical spine on labor and degenerative change of the cervical spine, and the factors affecting degenerative change of the cervical spine. MATERIALS AND METHODS: To determine the factors affecting degenerative change of the cervical spine, age, sex, height, weight, body mass index, smoking, diabetes mellitus (DM), time engaging in labor, and cervical spine posture (flexion or extension) required repetitively on labor were investigated in the subjects. In addition, to evaluate the level of degenerative change of the cervical spine on 83 people in the flexion group (flexion strain) and 83 people in the extension group (extension strain), cervical degenerative index (CDI) in the simple cervical spine lateral radiograph was used to score (0-60 points) the degenerative severity. RESULTS: A total of 166 subjects (flexion group: 83 people, extension group: 83 people) participated in this study, and for the CDI, the cervical spine flexion group scored 7.8±6.2 points, and the cervical spine extension group scored 12.2±6.0 points to show that the cervical spine extension group had significant degenerative change in the cervical spine. In the multiple linear regression test performed to verify the risk factors affecting the degenerative change of the cervical spine, age (p=0.004), contraction of DM (p=0.029), and extension posture of cervical spine (p<0.001) influenced the degenerative change of the cervical spine. CONCLUSION: Repetitive extension posture on the cervical spine on labor and contraction of diabetes affected degenerative change of the cervical spine, therefore, training in medical care and posture on labor are required to prevent the progression of degenerative change in the cervical spine.

Risk Factors of Cage Subsidence after Posterior Lumbar Interbody Fusion

STUDY DESIGN: Retrospective study. OBJECTIVES: The purpose of this study was to evaluate risk factors for subsidence after posterior lumbar interbody fusion (PLIF). SUMMARY OF LITERATURE REVIEW: Body mass index (BMI), bone mineral density (BMD), cage characteristics (titanium or poly-ether-ether-ketone (PEEK)) and degree of disc distraction are risk factors for cage subsidence after PLIF. MATERIALS AND METHODS: From January 2010 to January 2015, a total of 69 patients (93 segments) who were diagnosed with degenerative lumbar spine disease at the current authors' institution and underwent follow-up for at least 1 year were included in this retrospective study. Data on all factors related to cage subsidence were taken into consideration. The degree of association for each of the factors was determined through the calculation of odds ratios (ORs) with a 95% confidence interval. Logistic regression analyses were performed. The P-value that represented statistical significance was set below 0.05. RESULTS: There were no significant associations between fused segment level and cage subsidence (p=0.588), nor were there any significant associations between the kind of cage (titanium or PEEK) and cage subsidence (p=0.371). Using logistic regression, the factors with a P-value below the 0.20 level in univariate analyses were included in the multivariate analyses. In multivariate analyses, diabetes mellitus (DM) (p=0.029, OR, 4.524), osteoporosis (p=0.026, OR, 6.046), and degree of disc distraction (p=0.010, OR, 1.446) had significant associations with cage subsidence. In addition, there were significant associations between cage subsidence and instrument failure (p=0.008, OR, 8.235). CONCLUSIONS: DM and osteoporosis, which may affect bony structures, have significant associations with cage subsidence after PLIF. Cage insertion with excessive disc distraction during surgery may also affect cage subsidence after PLIF.

Spinal Epidural Abscess and Psoas Abscess Combined with Pyogenic Spondylodiscitis Following Vertebroplasty: A Case Report

STUDY DESIGN: Case report. OBJECTIVES: To report a case of extensive spinal epidural abscess and bilateral psoas abscesses combined with pyogenic spondylodiscitis after a L3 vertebroplasty. SUMMARY OF LITERATURE REVIEW: Infection after vertebroplasty or kyphoplasty is a rare medical complication. Few reports on spinal epidural abscess and bilateral psoas abscesses, coupled with pyogenic spondylodiscitis after vertebroplasty, are available in the English medical literature. MATERIALS AND METHODS: The authors performed a clinical and radiographic case review. RESULTS: A 74-year-old woman, without any existing medical illness, presented with a history of three weeks of lower back pain, fever, and neurologic deficits of both legs after vertebroplasty performed in another hospital. Magnetic resonance imaging demonstrated an extensive spinal epidural abscess from T10 to S1 and huge bilateral psoas abscesses combined with spondylodiscitis at L3-4. Urgent limited laminectomies and abscess drainage were performed from L1 to S1. The day after the operation, ultrasound-guided percutaneous drainage was performed to manage bilateral psoas abscesses. Methicillin-resistant Staphylococcus aureus was identified by intraoperative culture. Antibiotic therapy during hospitalization was maintained for six weeks with vancomycin and rifampicin. The infection was successfully treated without any neurologic deficit and spinal deformity. CONCLUSIONS: Vertebroplasty is relative safe and simple procedure; however, the procedure also may cause severe spinal infection. Aseptic techniques under sterile environment was required during surgery. It is important that early diagnosis and prompt surgical decompression in spinal epidural abscess with neurologic deficit. Limited surgery and antibiotic therapy could be a good treatment option in spinal epidural abscess combined with pyogenic spondylodiscitis.

Radiographic Analysis of Tibial-Articular Surface Angle According to the Selection of the Mechanical Axis / 대한족부족관절학회지

PURPOSE: We investigated a statistical difference of tibial-articular surface (TAS) angles between radiographs of standing ankle anteroposterior (AP) and whole lower extremity view, and evaluated whether the tibial axis obtained from the standing ankle AP view reflects the original mechanical axis of lower extremity. MATERIALS AND METHODS: Both the standing ankle AP and whole lower extremity view were taken from 60 legs of 30 healthy volunteers without a history of ankle surgery or deformity of lower limb. To determine the tibial axis, Takakura's and Hintermann's method were employed in the standing ankle AP view. To compare these results with the original TAS angle, ANOVA and multiple comparison test were used. RESULTS: The mean TAS angle was 88.3 degrees(from hip joint to ankle), 89.5 degrees (from knee joint to ankle), 88.5 degrees (Takakura's method), and 90.2 degrees(Hintermann's method). Although there was a statistical significance (p=0.000) between these results, Takakura's method had no significant difference, compared to the results of whole extremity view by the multiple comparison test. CONCLUSION: The tibial axis obtained by Takakura's method reflects the original mechanical axis of lower extremity. When a surgical procedure is planned, however, it is necessary to consider that the ankle radiographs do not provide any information on the proximal deformity without the whole lower extremity view.

Ossifying Lipoma in the Groin / 대한정형외과학회잡지

It is extremely rare to observe ossifying lipoma that developes separately from bone tissues in the groin. A patient with an adult fist-sized, firm, non-movable and painless mass in the left groin area, had been treated with marginal excision, which turned out to be ossifying lipoma. Although many different variants of lipoma with bone tissue have been reported, a case like this has never previously been reported. It is important to distinguish ossifying lipoma, from tumors with calcific lesions. We report its uniqueness in radiologic and pathologic ways, with specific findings of ossifying lipoma.

Therapeutic Embolization for Pseudoaneurysm of the Anterior Tibial Artery after Tibial Nailing / 대한정형외과학회잡지

Closed intramedullary nailing is a favorite surgical technique for tibial shaft fracture. After closed interlocking intramedullary nailing, proximal and distal locking screws are inserted for increasing rotational force and axial stability. Vascular complications associated with tibial nailing for fractures are very rare. Here, we described a case of a pseudoaneurysm of the anterior tibial artery after tibial nailing. We opted for minimally invasive treatment consisiting of thrombin injection and vascular plug insertion. Because pseudoaneurysm of the anterior tibial artery can induce severe complications, one should, when performing closed intramedullary nailing, make a quick diagnosis and start treatment right away.

A comparison of the hemodynamic changes and propofolinduced pain at two different doses of remifentanil in elderly patients / 대한마취과학회지

BACKGROUND: The purpose of this study was to determine the optimal dose of remifentanil for minimizing hemodynamic changes during intubation and reducing propofol-induced pain in elderly patients. METHODS: In a randomized prospective study, 60 patients (ASA I-II, elder than 65 years) were enrolled to determine which of two target remifentanil blood concentrations (3 ng/ml, 5 ng/ml) was required to blunt hemodynamic changes during intubation and to reduce propofol-induced pain. After the target effect site concentration of remifentanil had been reached, the target controlled infusion of propofol was started and propofol-induced pain was recorded. Blood pressure and heart rate were recorded at baseline, just before intubation and 1, 3, 5 min after intubation. RESULTS: There were no significant differences in the hemodynamic parameters between two groups, but not in arterial pressure at just before intubation and 1 minute after intubation. However, the group R5 (5 ng/ml) showed significantly less intense pain induced by propofol than in the group R3 (3 ng/ml). CONCLUSIONS: The results suggest that the group R5 provide more relief in propofol induced pain than the group R3, but showed great possibility of hypotension and bradycardia in both groups, which means it should be used with cautions in the elderly patients.

Poland Syndrome: A Case Report

PURPOSE: Poland syndrome is rare disease which is characterized by absence of unilateral pertoralis major muscle accompanied by ipsilateral syndactyly or brachydactyly, which was described first by Alfred Poland in 1841. MATERIALS AND METHODS: We performed the physical examination, laboratory test and radiologic evaluation to 18 year old male, who complaint asymmetry of right anterior chest. RESULTS: We diagnosed the Poland syndrome due to absence of right pectoralis major muscle and brachydactyly of right hand. CONCLUSION: Current authors report a patient who had hypopalsia of pectoralis muscles, which needed differential diagnosis with pectoralis major rupture.

Revision Total Knee Arthroplasty with a Cemented Posterior Stabilized, Condylar Constrained or Fully Constrained Prosthesis: A Minimum 2-year Follow-up Analysis

BACKGROUND: The clinical and radiological outcomes of revision total knee arthroplasty with a cemented posterior stabilized (PS), condylar constrained knee (CCK) or a fully constrained rotating hinge knee (RHK) prosthesis were evaluated. METHODS: This study reviewed the clinical and radiological results of 36 revision total knee arthroplasties with a cemented PS, CCK, and RHK prosthesis in 8, 25, and 13 cases, respectively, performed between 1998 and 2006. The mean follow-up period was 30 months (range, 24 to 100 months). The reason for the revision was aseptic loosening of one or both components in 15, an infected total knee in 18 and a periprosthetic fracture in 3 knees. The average age of the patients at the time of the revision was 65 years (range, 58 to 83 years). The original diagnosis for all primary total knee arthroplasties was osteoarthritis except for one case of a Charcot joint. All revision prostheses were fixed with cement. The bone deficiencies were grafted with a cancellous allograft in the contained defect and cortical allograft fixed with a plate and screws in the noncontained defect. A medial gastrocnemius flap was needed to cover the wound dehiscence in 6 of the 18 infected cases. RESULTS: The mean Knee Society knee score improved from 28 (range, 5 to 43) to 83 (range, 55 to 94), (p < 0.001) and the mean Knee Society function score improved from 42 (range, 10 to 66) to 82 (range, 60 to 95), (p < 0.001) at the final follow-up. Good or excellent outcomes were obtained in 82% of knees. There were 5 complications (an extensor mechanism rupture in 3 and recurrence of infection in 2 cases). Three cases of an extensor mechanism defect (two ruptures of ligamentum patellae and one patellectomy) were managed by the RHK prosthesis to provide locking stability in the heel strike and push off phases, and two cases of recurrent infection used an antibiotic impregnated cement spacer. The radiological tibiofemoral alignment improved from 1.7degrees varus to 3.0degrees valgus in average. Radiolucent lines were observed in 18% of the knees without progressive osteolysis. CONCLUSIONS: Revision total knee requires a more constrained prosthesis than primary total knee arthroplasty because of the ligamentous instability and bony defect. This short to midterm follow-up analysis demonstrated that a well planned and precisely executed revision can reduce pain and improve the knee function significantly. Infected cases showed as good a result as those with aseptic loosening through the use of antibiotics-impregnated cement beads and proper soft tissue coverage with a medial gastrocnemius flap.

Os Trigonum Syndrome with Posterolateral Osteochondral Lesion of Talus (A Case Report) / 대한족부족관절학회지

Both os trigonum syndrome and osteochondral lesion of talus (OLT) are common causes of ankle pain and usually affect ballet dancers or athletes. Lateral osteochondral lesions, which usually result from traumatic event, are mostly located anterolateral talar dome but rare central or posterolateral. Moreover, there are technical difficulties such as position of patient or additional posterior portal to address posterolateral lesion by arthroscopy. Meanwhile, treatment of os trigonum syndrome using arthroscopic approach has been reported in many literatures recently. However, it has not been reported to diagnose both os trigonum syndrome and posterolateral OLT together and treat arthroscopically at one stage. The authors report a case of male patient who was diagnosed as os trigonum syndrome with posterolateral OLT and treated simultaneously by hindfoot arthroscopy. Symptom was improved immediately after the operation, and radiological findings at postoperative 16 months verified remarkable healing.

Posterior Lumbar Interbody Fusion Using a Unilateral Single Cage and a Local Morselized Bone Graft in the Degenerative Lumbar Spine

BACKGROUND: We retrospectively evaluated the clinical and radiological outcomes of posterior lumbar interbody fusion (PLIF) with using a unilateral single cage and a local morselized bone graft. METHODS: Fifty three patients who underwent PLIF with a unilateral single cage filled with local morselized bone graft were enrolled in this study. The average follow-up duration was 31.1 months. The clinical outcomes were evaluated with using the visual analogue scale (VAS) at the pre-operative period, at 1 year post-operation and at the last follow-up, the Oswestry Disability Index, the Prolo scale and the Kim & Kim criteria at the last follow-up; the radiological outcomes were evaluated according to the change of bone bridging, the radiolucency, the instablity and the disc height. RESULTS: For the clinical evaluation, the VAS pain index, the Oswestry Disability Index, the Prolo scale and the Kim & Kim criteria showed excellent outcomes. For the the radiological evaluation, 52 cases showed complete bone union at the last follow-up. Regarding the complications, only 1 patient had cage breakage during follow-up. CONCLUSIONS: PLIF using a unilateral single cage filled with a local morselized bone graft has the advantages of a shorter operation time, less blood loss and a shorter hospital stay, as compared with the PLIF using bilateral cages, for treating degenerative lumbar spine disease. This technique also provides excellent outcomes according to the clinical and radiological evaluation.

Popliteal Artery Entrapment Syndrome: A Case Report

Popliteal artery entrapment syndrome is an infrequent disease that usually occurs in relatively young patients. The authors encountered a case of unilateral popliteal artery occlusion caused by anomalous slippage of the medial head of the gastrocnemius muscle. Complete resection of the occluded segment and myotomy of the anomalous slip were performed, and end-to-end re-anastomosis was completed using a saphenous vein graft. At 18 months after the procedure, there was no evidence of recurrence.

Spontaneous Spinal Epidural Hematoma of the Thoracic Spine in Young Adult: A Case Report / 대한척추외과학회지

A spontaneous spinal epidural hematoma (SSEH) of the thoracic spine is a rare space-occupying disease that accompanied with severe axial pain in the spine. Because there is the possibility of a significant neurological injury such as paraplegia, SSEH requires careful diagnosis and management. A SSEH is mainly caused by a coagulating disorder or anticoagulant medication, while certain cases have shown that this disease is related with spinal inflammatory conditions. A SSEH tends to occur in patients who have risk factors for hemorrhage. However, the incidence of SSEH is quite low, and there are few domestic reports of a SSEH in young adults who are without the risk factors for hemorrhage. We encountered a 25 years old young male without a prior significant medical history and he was suffering from severe back pain and paraplegia due to a SSEH at the thoracic spine. The early diagnosis was made via MRI. We report here on a favorable clinical outcome that was achieved with immediate operative treatment, and we include a review of the relevant literature.

Effectiveness of the New Modified Smith-Robinson Bone Graft for Cervical Anterior Interbody Fusion / 대한정형외과학회잡지

PURPOSE: We attempted to evaluate the effectiveness of the new modified Smith-Robinson bone graft method for performing cervical anterior interbody fusion. MATERIALS AND METHODS: Forty-two patients had anterior interbody fusion on the cervical spine, using an anterior approach and the new modified Smith-Robinson's method (NMSR), between September 2001 and June 2006. There were 30 males and 12 females, with an average age of 51.2 years and the mean follow up period was 39.5 months. We measured the area from C4 to C6 in 32 cases. This was compared with the contact area of the bone graft of the NMSR method and the Original Smith-Robinson method (OSR). We also checked the time to bone union and changes of Cobb's angle at the final follow-up to evaluate the effectiveness of the NMSR. RESULTS: Bony fusion was obtained in all cases. The average size of the OSR were 169 and 152 mm2, in the males and females respectively, whereas those of the NMSR were 263, and 228 mm2. Therefore, the average size of the NMSR increased to 94 mm2 and 76 mm2 than those of the OSR method in the males and females. The average time to radiological bone union was 9.6 weeks and the changes of Cobb's angle at final follow-up were 2.5+/-2.6degrees. CONCLUSION: The NMSR technique was a very effective method for cervical anterior interbody fusion. It could enlarge the bone graft size about 50-56% compared with the OSR technique. It also shortened the period of bone union and also increased the bone union rate.

Revision Total Hip Replacement using a Cementless Wagner SL Femoral Stem

PURPOSE: To evaluate the clinical and radiological changes of femoral revision with the Wagner SL stem. MATERIALS AND METHODS: 21 femoral revisions were performed in 21 patients (16 males and 5 females; mean age 58.9 years) between June 1997 and July 2005, utilizing the Wagner SL stem. The follow-up period was a mean of 31 months (range 25-84 months). Causes of revision included aseptic loosening (14 cases), periprosthetic fracture (4 cases), recurrent total hip dislocation (2 cases), and neglected bipolar hip dislocation (1 case). Greater trochanteric osteotomy was performed in 10 cases, and extended trochanteric osteotomy was performed in 6 cases. Clinical results were assessed using Harris hip score. Radiographic parameters such as stem subsidence, calcar atrophy, and stressshielding were also assessed. RESULTS: The mean Harris hip score improved from 45.7 to 91.3. There was no removal of the implanted Wagner stem. One case of nonunion of the greater trochanter was treated by fixation with Dall-Miles cables and a trochanteric plate. There was one case of limb shortening of 2 cm. CONCLUSION: The Wagner SL stem provided immediate stability and allowed early weight-bearing. Bony regeneration around the stem was achieved without resorting to a bone graft.

The Change of Stress Distribution according to Fixation Devices and Osteotomy Methods in High Tibial Osteotomy / 대한정형외과연구학회지

PURPOSE: To evaluate the necessity of lateral translation and the primary stability of the fixation devices in a closed wedge high tibial osteotomy. MATERIALS AND METHODS: The authors studied four pairs of high tibial osteotomy: Pair I, lateral translation with blade plate fixation; Pair II, lateral translation with staple fixation; Pair III, no translation with blade plate fixation; Pair IV, no translation with staple fixation. Four models of bovine tibia were taken and analyzed for stress distribution at the osteotomy site under axial loading. After axial loading, information recorded in pressure sensitive film was transformed to image file. After, by using image analysis software, the mean stress value and maximum stress value was calculated. RESULTS: The mean stress calculated at each osteotomy site is as follows; 3.89 MPa in the first pair; 4.55 MPa in the second pair; 4.62 MPa in the third pair; and 4.67 MPa in the fourth pair. In Group I, stress value was distributed evenly. But in group II, III, IV, the stress was concentrated at posteromedial area of the osteotomy site. CONCLUSION: The primary in the high tibial osteotomy was dependent more on the rigid fixation than on the continuity of the medial cortex. The pairs on which blade plate fixation was used more stable than the pairs on which staple fixation was used regardless of lateral translation.