Chang-Wug Oh

Distal tibia metaphyseal fractures treated by percutaneous plate osteosynthesis.

Twenty-one patients with fractures of the distal tibial metaphysis, some with minimal displacement in the ankle, were treated by percutaneous plate osteosynthesis with a narrow limited contact-dynamic compression plate. Using the classification by the Arbeitsgemeinschaft für Osteosynthesefragen and Orthopaedic Trauma Association, 17 fractures had no articular involvement, whereas four included intraarticular extension. At final followup (mean, 20 months), all the fractures healed without second procedures and the mean union time was 15.2 weeks. One patient had malalignment of the limb with 10° internal rotation, but there were no angular deformities greater than 5° or any shortening greater than 1 cm. All patients had excellent or satisfactory ankle function. There were no infections or any soft tissue compromise. Percutaneous plate osteosynthesis is a safe and worthwhile method of managing such fractures, which avoids some of the complications associated with conventional open plating methods.

Comparison of internal bone transport and vascularized fibular grafting for femoral bone defects.

Objective To compare results between vascularized fibular grafting and internal bone transport for large bone defects of the femur. Design Retrospective review of patients. Setting University teaching hospitals. Patients This study included 37 patients with femoral bone loss: 20 patients were treated with internal bone transport and seventeen patients were treated with vascularized fibular grafting. Main Outcome Measurements The outcomes investigated were external fixation time, external fixation index, bone results (union, infection, deformity, leg length discrepancy), and functional results. Results The mean amount of filled defect was 8.4 cm with internal bone transport and 8.9 cm with vascularized fibular grafting. The external fixation index was 1.4 months/cm with internal bone transport and 1 month/cm with vascularized fibular grafting. The bone results and functional results of the internal bone transport were excellent in 65% and 0%, good in 5% and 45%, fair in 5% and 40%, poor in 25% and 15%, respectively, whereas those of the vascularized fibular grafting were excellent in 35% and 0%, good in 25% and 47%, fair in 5% and 35%, and poor in 35% and 18%. Conclusion With vascularized fibular grafting, careful monitoring of circulation and early intervention surgery is necessary to avoid vascular failure. With internal bone transport, repeated radical debridement until control of infection is achieved, bone grafting at the docking site for early union, and avoiding stress fracture are recommended to improve bone results.

The biomechanical performance of locking plate fixation with intramedullary fibular strut graft augmentation in the treatment of unstable fractures of the proximal humerus

We evaluated the biomechanical properties of two different methods of fixation for unstable fractures of the proximal humerus. Biomechanical testing of the two groups, locking plate alone (LP), and locking plate with a fibular strut graft (LPSG), was performed using seven pairs of human cadaveric humeri. Cyclical loads between 10 N and 80 N at 5 Hz were applied for 1,000,000 cycles. Immediately after cycling, an increasing axial load was applied at a rate of displacement of 5 mm/min. The displacement of the construct, maximum failure load, stiffness and mode of failure were compared. The displacement was significantly less in the LPSG group than in the LP group (p = 0.031). All maximum failure loads and measures of stiffness in the LPSG group were significantly higher than those in the LP group (p = 0.024 and p = 0.035, respectively). In the LP group, varus collapse and plate bending were seen. In the LPSG group, the humeral head cut out and the fibular strut grafts fractured. No broken plates or screws were seen in either group. We conclude that strut graft augmentation significantly increases both the maximum failure load and the initial stiffness of this construct compared with a locking plate alone.

Percutaneous Screw Fixation for Scaphoid Fracture: A Comparison Between the Dorsal and the Volar Approaches

PURPOSE To evaluate the position of the screws and find the difference of clinical and radiologic outcome between the volar approach and the dorsal approach groups in percutaneous screw fixation for acute scaphoid fractures. METHODS Forty-one consecutive patients with an acute scaphoid fracture, who had percutaneous fixation via either the volar approach or the dorsal approach, were evaluated at an average of 30 months after the surgery. The volar approach was used in 19 patients and the dorsal approach in 22 patients. By using a computerized digital image program, angles between the Herbert screw with respect to the long axis of the scaphoid and the fracture line were measured with plain radiographs in the posteroanterior, lateral, and the 45 degrees semipronated oblique views. RESULTS The screws showed no significant difference between the 2 groups in posteroanterior and lateral views; however, screws in the dorsal approach group were observed to be placed more parallel to the long axis of the scaphoid in the semipronated oblique view. The screws in the dorsal approach group were positioned more perpendicular to the fracture lines of the scaphoid compared with those of the volar approach group for all 3 different radiographic views. There was no statistically significant difference between the 2 treatment groups regarding fracture healing. According to the Mayo wrist score system, excellent results were recorded in 18 patients in the dorsal approach group and 15 patients in the volar approach group. CONCLUSIONS This study suggests that screws are placed more parallel to the long axis of the scaphoid and perpendicular to the fracture line via the dorsal approach; however, there was no significant difference with regard to functional outcome and bone union. TYPE OF STUDY/LEVEL OF EVIDENCE Therapeutic IV.

Early failure of hemispheric hydroxyapatite-coated acetabular cups.

Total hip arthroplasties with hydroxyapatite coatings have shown encouraging results after early-term followup. We presumed hydroxyapatite-coating on a smooth hemispheric press-fit acetabular cup would enhance bone osseointegration and maintain stability of cup after midterm (minimum 5-year) followup. Sixty-three patients had 70 consecutive total hip arthroplasties. Five patients (eight hips) died from problems unrelated to surgery. The remaining patients (62 hips) were followed up for an average of 7 years (range, 6-9 years). The mean age of the patients was 49 years (range, 23-61 years). The average Harris hip score improved from 59 points (range, 32-82 points to 82 points (range, 37-100 points) at final followup. There were seven acetabular component revisions. Of the 55 unrevised cups, 47 hips (85%) were stable by bony ingrowth, five hips (9%) were fibrous stable, and three hips (5%) were unstable with cup migration. Osteolysis around the cup was observed in 18 hips (33%). The average polyethylene wear rate was 0.15 mm/year. Survival rates of the cups at 6 and 8 years were 94.3% and 60.5%, respectively. Total hip arthroplasties using an hydroxyapatite-coated smooth hemispheric acetabular cup showed an unexpected high failure rate in terms of fixation, occurrence of osteolysis, and revision after midterm followup.Level of Evidence: Therapeutic study, Level IV (case series). See the Guidelines for Authors for a complete description of levels of evidence.

Plating of humeral shaft fractures: comparison of standard conventional plating versus minimally invasive plating.

PURPOSE This study compared clinical outcomes and complications in patients with humeral shaft fractures treated using two methods of fixation by plating. METHODS Minimally invasive plate osteosynthesis (MIPO, n=29) was prospectively performed from around the middle of the study period, while open reduction and plate osteosynthesis (ORPO, n=30) had been the original standard method. Locking compression plate was used in these two groups. Major characteristics of the two groups were similar in terms of fracture type, fracture location, age, associated injuries and numbers of open fractures. RESULTS Primary union was achieved in 28 of 29 in the MIPO and in 27 of 30 in the ORPO. Mean time to union was similar in the two groups. Mean operation time in the MIPO (110min) was shorter than in the ORPO (169min) (P<0.05). Bone grafting was performed in five patients of in the ORPO, but in no patient in the MIPO (P<0.0001). There was one case of deep infection in the ORPO. Functional outcome was satisfactory in both groups. CONCLUSIONS Minimally invasive plate osteosynthesis may achieve comparable results with the open plate osteosynthesis method in simple as well as complex fractures of humeral shaft. Although MIPO potentially has the radiation hazard, it may reduce the perioperative complications with a shortened operation time. LEVEL OF EVIDENCE Level III. Case-control study.

Fourth Brachymetatarsia Treated with Distraction Osteogenesis

Background: This study investigated metatarsal lengthening by distraction osteogenesis for fourth brachymetatarsia in 22 metatarsals (16 patients). Methods: From May 1997 to May 2000, lengthening was performed with a monoexternal fixator, and distraction was started at a rate of 0.5 mm per day after a latency period of approximately 7–10 days. Results: The average gain in length was 16.5 mm (range, 13–21 mm), equivalent to an increase of 39% (range, 28–51%), and the average healing index was 72.9 days/cm (range, 51.7–95.7 days/cm). The American Orthopaedic Foot and Ankle Society (AOFAS) average score for lesser toe was 86.3 (range, 47–100). The most common residual complication was subluxation of metatarsophalangeal (MTP) joint in five cases, with partial or total stiffness of the MTP joint. These complications happened in the group of metatarsals excessively lengthened more than 40% and made the AOFAS score poorer. The other complications were three cases of angular deformity in the lengthened bone, and two cases of pin-tract infection. Conclusion: Although distraction osteogenesis is an effective method to address fourth brachymetatarsia, stiffness or subluxation of the MTP joint was not uncommon. To avoid complications that can happen as a result of excessive lengthening, careful preoperative radiographic measurement to calculate the optimal amount of lengthening may help us to avoid over-lengthening and the complications that accompany it.

A prospective randomized study of operative treatment for noncomminuted humeral shaft fractures: conventional open plating versus minimal invasive plate osteosynthesis.

Objectives: To compare the clinical and radiologic results of conventional open plating (COP) and minimally invasive plate osteosynthesis (MIPO) in the treatment of noncomminuted humeral shaft fractures. Design: Randomized prospective study. Setting: Five level 1 trauma centers. Patients: Sixty-eight consecutive patients were randomized into 2 study groups: those treated by COP (COP group; n = 32) and those treated by MIPO (MIPO group; n = 36). Intervention: Simple humeral shaft fractures (AO/OTA classification types A and B) were reduced by open reduction or closed reduction and fixed with a narrow 4.5/5.0 locking compression plate, metaphyseal locking compression plate, or proximal humeral internal locking system plate to the anterior lateral aspect of the humerus. Main Outcome Measurements: Fracture healing time, operative time, radiation exposure time, and intraoperative nerve injury. To assess shoulder and elbow function, we used the University of California, Los Angeles (UCLA) scoring system and the Mayo elbow performance index, including the range of motion and pain. Radiographic measurements included fracture alignment, delayed union, and nonunion. Results: Thirty-one fractures (97%) healed in the COP group within 16 weeks, whereas 36 fractures (100%) were healed in the MIPO group by 15 weeks. No significant difference was observed in the operative time or complication rates. In both groups, all fractures achieved union without malunion and with excellent functional outcomes by definition of the Mayo elbow performance index and UCLA scoring system. Conclusions: This study confirmed a high overall rate of union and excellent functional outcomes in both MIPO and COP groups. MIPO is equivalent to COP as a safe and effective method for simple types of humeral shaft fractures when surgery is indicated, and the surgeon is experienced in the technique. Level of Evidence: Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Epidemiology and demographics of slipped capital femoral epiphysis in Korea: a multicenter study by the Korean Pediatric Orthopedic Society.

Background In 1979, slipped capital femoral epiphysis (SCFE) was rarely reported in Korea, although it is the most common hip disorder of adolescence in Western nations. However, because the number of reported cases of SCFE in Korea has increased a great deal since then, we performed a nationwide survey to ascertain its epidemiology and demographics in Korea. Methods We reviewed the discharge databases for the period between January 1989 and December 2003 from 19 university hospitals across Korea. Recorded data included age at onset, sex, past medical history, height, weight, and type of slippage. We compared those data with national census data. The incidence data are reported as cases per 100,000 children between the ages of 10 and 14 years. Results Data for 231 patients (175 boys and 56 girls) were included in our survey. The average age at onset was 12 years 10 months in boys and 12 years in girls. The average annual incidence was estimated to be at least 0.499 for boys and 0.142 for girls for every 100,000 children between the ages of 10 and 14 years, which was lower than that of Western nations and Japan. The incidence showed a pattern of increments across each period. The mean body mass index was significantly higher in Korean patients with SCFE than in the population of the same age group without it. Conclusions The incidence of SCFE in preadolescents in Korea has increased markedly since 1979, which may be related to increasing rates of obesity. Level of Evidence Therapeutic, level 4.

Limb lengthening with a submuscular locking plate

Ten patients, who were unsuitable for limb lengthening over an intramedullary nail, underwent lengthening with a submuscular locking plate. Their mean age at operation was 18.5 years (11 to 40). After fixing a locking plate submuscularly on the proximal segment, an external fixator was applied to lengthen the bone after corticotomy. Lengthening was at 1 mm/day and on reaching the target length, three or four screws were placed in the plate in the distal segment and the external fixator was removed. All patients achieved the pre-operative target length at a mean of 4.0 cm (3.2 to 5.5). The mean duration of external fixation was 61.6 days (45 to 113) and the mean external fixation index was 15.1 days/cm (13.2 to 20.5), which was less than one-third of the mean healing index (48 days/cm (41.3 to 55). There were only minor complications. Lengthening with a submuscular locking plate can successfully permit early removal of the fixator with fewer complications and is a useful alternative in children or when nailing is difficult.