Results of Primary Total Knee Arthroplasty in Osteoarthritis with Varus Thrust Knee and Severe Varus Deformity / 대한정형외과학회잡지

Purpose@#Varus thrust is an posterolateral rotatory knee motion observed with severe varus patients. It shows a dynamic worsening of varus in the loading response (LR), while returning to a more neutral alignment during the initial contact (IC) of gait. This study examined the results of primary total knee arthroplasty in varus thrust osteoarthritis, including varus thrust motion, gait analysis. @*Materials and Methods@#From March 2009 to March 2019, among 2,391 total knee arthroplasty who underwent total knee arthroplasty, 84 knees from 68 patients with varus thrust and more than a 20° varus deformity were enrolled in this study. The pre-operative and postoperative varus thrust amount (VTA), proximal tibiofibular overlap (PTFOL), and implant position (α, β, γ, and δ) were examined. The gait pattern was analyzed before and after surgery using the footscan ® (RSscan International, Olen, Belgium), evaluating the foot axis-center of pressure angle (FCA) of the ipsilateral foot at the IC and at the LR. The clinical outcomes were evaluated with Hospital for special surgery (HSS). @*Results@#The changes in the VTA were from a pre-operative mean of 5.1° (3.1–7.2) to a mean of 1.9° (0.3–2.8) at the last follow-up (p=0.017). PTFOL changed from pre-operative mean of 18.1 mm (9.0–29.1) to post-operative mean of 11.0 mm (4.2–20.7) (p=0.029). The mean α, β, γ, and δ angle in the last follow-up was 94.6°, 90.3°, 3.86°, and 89.7°, respectively. The FCA in IC was corrected from a pre-operative mean of -1.8° (-1.0 to -4.4) to a post-operative mean of 2.3° (-1.1 to 4.1) (p=0.013). FCA in LR was similar from a pre-operative mean of 5.2° (1.0–7.2) to a post-operative mean of 6.0° (1.1–7.4) (p=0.823). The HSS was changed from a pre-operative mean of 45.7 to a post-operative mean of 86.2 in the last follow-up (p=0.011). @*Conclusion@#Standard total knee arthroplasty in the varus thrust knee showed satisfactory correction of the varus thrust amount and gait pattern, without recurrence of the varus thrust gait. Better clinical results were achieved in total knee arthroplasty of osteoarthritis with a varus thrust without using a constraining implant.

Results of a Bioabsorbable Magnesium Screw and K-Wire for the Surgical Treatment of an Upper Extremity Fracture / 대한정형외과학회잡지

Purpose@#The treatment of fractures has shown excellent safety enabling solid fixation and early exercise treatment with the development of internal metal fixtures and fixation techniques. On the other hand, complications remain, such as secondary surgery for implant removal and, discomfort caused by internally fixed metal materials. Recently, a bioabsorbable magnesium implant with relatively high strength and low decomposition, manufactured using only body components, was developed in the form of screws and K-wire for use in orthopedic surgery. This study aimed to apply bioabsorbable magnesium screws and K-wires to upper extremity fracture surgery and investigate the results. @*Materials and Methods@#From May 2019 to September 2019, 46 cases (clavicle 11, humerus 4, olecranon 2, radial head 4, coronoid process 3, radius 4, ulna 1, phalanx 8, metacarpals 8, and hamate 1) in 44 patients who agreed to use a bioabsorbable magnesium implant among patients requiring internal fixation using screws and K-wires for upper extremity fractures at the author’s orthopedic surgery department were enrolled. The U&I Corporation commissioned this study, and a prospective study was conducted. The radiological findings and The Disabilities of the Arm, Shoulder, and Hand (DASH) score, hydrogen gas generation, and complications were evaluated. In comminuted fractures, the magnesium screws and K-wires were used for additional interfragmentary fixation with a conventional metal plate and screws in 22 cases. There were 24 cases of exclusive usage. The most common surgical method was intramedullary fixation of bioabsorbable magnesium K-wires in 10 cases. @*Results@#In all cases, bone union was achieved on average 16 weeks (4–28 weeks) after surgery, and the mean DASH score at the last follow-up was 45.0 (30–116). A hydrogen gas cavity produced around the absorbable magnesium implant was observed at an average of two weeks and six days, and the largest was noted at an average of 12 weeks. There were no interactive reactions with drugs, infection, osteolysis, tendon rupture and swelling with hydrogen gas. There were two cases of the loss of reduction, one case of implant breakage, two cases of urticaria. @*Conclusion@#Bioabsorbable magnesium screws and K-wires can be applied for upper extremity fractures, but caution is required.

The Fixation Method according to the Fracture Type of the Greater Trochanter in Unstable Intertrochanteric Fractures Undergoing Arthroplasty / 대한고관절학회지

PURPOSE: We conducted a study on patients who underwent hip joint arthroplasty because of unstable femur intertrochanteric fractures with greater trochanter bony fragments. After dividing patients into three groups depending on their fracture patterns, we evaluated the clinical and radiological outcomes of different operation methods applied to each of these groups. MATERIALS AND METHODS: Using Evan's classification, we defined an unstable intertrochanteric fracture as those characterized as stage 4 or 5. Of the 137 patients presenting with an intertrochanteric fracture with osteoporosis (bone mineral density, <−2.5) between March 2014 and October 2015, 63 met the eligibility criteria and were included in this study. Next, patients were divided into three groups based on their greater trochanter fracture patterns (discerned with three-dimensional computed tomography images); different fixation methods were applied to each group by a single orthopaedic surgeon. RESULTS: Taken as a whole, 50 out of 63 patients experienced no reduction in walking distance in their daily lives. Harris hip score increased from 74.8 to 85.7 point and we considered this a relatively good result. Radiologically, we observed complete bone union in 62 cases (98.4%); the lone exception was in a patient who experienced osteolysis. There were also 3 cases who removed greater trochanter reattachment device due to broken implant and 1 case of dislocation. CONCLUSION: The different fixation methods applied to three distinct groups with varying fractures patterns were successful in achieving proper reduction and fixation of greater trochanteric fractures. We also observed reduced bone union periods when arthroplasty was performed in patients with unstable intertrochanteric fractures. Lastly, we believe these approaches may also aid in achieving early ambulation and early rehabilitations.

Treatment of Wide Gap Non-Unions in Lower Extremities

PURPOSE: To analyze the end results of the treatment for patients with wide gap non-unions of the long bones in the lower extremities. MATERIALS AND METHODS: A total of 62 cases of wide gap unions, with a mean age of 38 years, were included for analysis. Study cohort included six children under the age of seven years. The average size of established bone defect was 7 cm (4-23 cm). Bone defects under 7 cm were treated with plating and various bone grafts, and those over 7 cm were managed with vascularized fibular graft (VFG), distraction-osteogenesis, tibial strut, plating and etc. Two boys with a defect of the whole tibia but with an intact fibula were treated with tibialization of intact fibula and with rotation-plasty of the leg. Their end results were evaluated by the time of bony union in accordance with the treatment of defect size of the long bone as well as their age. RESULTS: Bony unions were obtained for an average period of at least 27 months. Fifty-one cases showed an average leg-length discrepancy of 2.8 cm, and 11 cases showed no leg-length discrepancy. The VFG, distraction-osteogenesis, and tibial cortical-strut graft and plating were the most effective methods for non-unions of wide, long bone defections (>7 cm). The prognosis was more favorable in children, muscular femur, and in cases with tibial defect but intact fí bula. CONCLUSION: Various bone union techniques should be considered carefully, considering the ages of patients and the size of bone defects. Due to severe physical and mental disabilities of patients during the long-treatment period, specialized orthopedic doctors for trauma and mental care were necessary.

Treatment of Wide Gap Non-Unions in Lower Extremities

PURPOSE: To analyze the end results of the treatment for patients with wide gap non-unions of the long bones in the lower extremities. MATERIALS AND METHODS: A total of 62 cases of wide gap unions, with a mean age of 38 years, were included for analysis. Study cohort included six children under the age of seven years. The average size of established bone defect was 7 cm (4-23 cm). Bone defects under 7 cm were treated with plating and various bone grafts, and those over 7 cm were managed with vascularized fibular graft (VFG), distraction-osteogenesis, tibial strut, plating and etc. Two boys with a defect of the whole tibia but with an intact fibula were treated with tibialization of intact fibula and with rotation-plasty of the leg. Their end results were evaluated by the time of bony union in accordance with the treatment of defect size of the long bone as well as their age. RESULTS: Bony unions were obtained for an average period of at least 27 months. Fifty-one cases showed an average leg-length discrepancy of 2.8 cm, and 11 cases showed no leg-length discrepancy. The VFG, distraction-osteogenesis, and tibial cortical-strut graft and plating were the most effective methods for non-unions of wide, long bone defections (>7 cm). The prognosis was more favorable in children, muscular femur, and in cases with tibial defect but intact fí bula. CONCLUSION: Various bone union techniques should be considered carefully, considering the ages of patients and the size of bone defects. Due to severe physical and mental disabilities of patients during the long-treatment period, specialized orthopedic doctors for trauma and mental care were necessary.