Utilizing Suture Anchors in Addition to Screws for Treatment of Tibial Tubercle Avulsion Fracture: A Case Report.

Tibial tubercle avulsion fractures are relatively uncommon fractures commonly seen in adolescent males. The treatment goal is to restore the extensor mechanism and to repair the articular surface. Although previous surgical techniques have been mainly screws or tension band wiring, there is a certain consensus on this. However, the choice of these surgical techniques largely depends on the surgeon. In our case, we utilized a suture anchor distal to the cannulated screw. This enabled us to use a smaller screw and cover the screw head completely with the patellar tendon. Therefore, this can be an advantage in lowering the incidence of device irritation. Given the successful outcome of our technique, we may consider applying suture anchors more frequently in tibial tubercle avulsion fractures in the future.

The tibial tubercle-to-trochlear groove distance changes in standing weight-bearing condition: An upright weight-bearing computed tomography analysis.

BACKGROUND: The tibial tubercle-to-trochlear groove (TT-TG) distance and Insall-Salvati (I/S) ratio are widely used to determine the need for distal realignment in conjunction with medial patellofemoral ligament (MPFL) reconstruction in patients with recurrent patellar dislocation. A TT-TG distance >20 mm and an I/S ratio >1.3 are significant anatomical risk factors for patellar instability. However, these parameters have traditionally been measured using non-weight-bearing (NWB) imaging modalities. As patellar dislocation occurs during weight-bearing actions, these two parameters should be measured under weight-bearing conditions. Thus, this study aimed to measure the TT-TG distance and I/S ratio using upright full-weight-bearing (FWB) computed tomography (CT) scans and compare the data with NWB CT scans. METHODS: This study included 49 knee joints of 26 healthy volunteers. CT images were obtained under both FWB and NWB standing conditions using a 320-detector row upright CT scanner. TT-TGs in the axial plane and I/S ratios in the sagittal plane were measured and compared. RESULTS: The average FWB TT-TG distance was 20.3 ± 3.9 mm, whereas the average NWB TT-TG distance was 12.3 ± 4.7 mm. The TT-TG level was significantly higher in the FWB condition than that in the NWB condition (P < 0.001). The I/S ratios were comparable between the FWB and NWB conditions (P = 0.29). CONCLUSIONS: The TT-TG distance in the standing weight-bearing condition was larger than the conventional TT-TG distance and surpassed the historical cutoff value of TT-TG, which may affect the indication of additional distal realignment in MPFL reconstruction for patellar instability.

Extra-articular location of the three-dimensional mechanical axis in advanced knee osteoarthritis: an upright computed tomography study.

PURPOSE: One of the most widely used benchmarks of lower-limb alignment is the mechanical axis (MA), which passes through the centers of the femoral head and the ankle in the weight-bearing position. However, where the MA passes through three-dimensionally (3D) is unclear. We investigated the MA in 3D (3D-MA) in knee osteoarthritis (OA) using upright computed tomography (CT). MATERIALS AND METHODS: This study included 66 varus OA knees from 38 patients [age 70.0 (64.8-77.0) years; median (interquartile range)]. The 3D-MA was determined using upright CT data and compared among Kellgren-Lawrence (KL) grades. Further, correlations between the 3D-MA and other parameters were evaluated. RESULTS: The 3D-MA was located at 5.3 (1.3-14.4)% medially and 7.1 (0.7-15.3)% posteriorly on the tibial plateau in KL-1, and was translated medioposteriorly with increased KL grade. The 3D-MA in KL-3 [30.6 (22.6-42.6)% medially and 50.9 (45.8-80.2)% posteriorly] and KL-4 [56.7 (48.5-62.9)% medially and 92.3 (50.2-127.1)% posteriorly] was located extra-articularly. The mediolateral position of the 3D-MA correlated with the femorotibial angle [correlation coefficient (CC) = - 0.85, p < 0.001], and the anteroposterior position of the 3D-MA correlated with the knee flexion angle (CC = - 0.93, p < 0.001). CONCLUSION: Our analysis demonstrated that the 3D-MA in low-grade OA knees passes slightly medial and posterior to the knee center, and the 3D-MA is translated medioposteriorly with the progression of knee OA. Further, the 3D-MA is translated medially with varus progression and posteriorly with the progression of knee flexion contracture.

Three-dimensional joint surface orientation does not correlate with two-dimensional coronal joint line orientation in knee osteoarthritis: Three-dimensional analysis of upright computed tomography.

BACKGROUND: Two-dimensional (2D) coronal joint line orientation on radiography under weight-bearing conditions has been widely used in evaluating knee osteoarthritis (OA). However, the effects of tibial rotation remain unknown. The present study aimed to newly define three-dimensional (3D) joint surface orientation relative to the floor as an unchangeable 3D angle unaffected by tibial rotation using upright computed tomography (CT), and to investigate correlations between 3D and 2D parameters in knee OA. METHODS: Sixty-six knees in 38 patients with varus knee OA underwent standing hip-to-ankle digital radiography and upright CT. The 2D parameters measured on radiographs included femorotibial angle (FTA), tibial joint line angle (TJLA), lateral distal femoral angle (LDFA), medial proximal tibial angle (MPTA), and joint line convergence angle (JLCA). The 3D inner product angle between vectors of the tibial joint surface and the floor from CT was defined as the 3D joint surface-floor angle. RESULTS: Mean 3D joint surface-floor angle was 6.0 ± 3.6°. No correlation was identified between 3D joint surface-floor angle and 2D joint line parameters, even though FTA correlated substantially with 2D joint line parameters. No significant differences in 3D joint surface-floor angle were identified among Coronal Plane Alignment of the Knee (CPAK) types. CONCLUSIONS: The 3D joint surface orientation did not correlate with 2D coronal joint line orientation and was unaffected by CPAK classification types. This finding suggests that current 2D evaluations should be reconsidered for a better understanding of true knee joint line orientation.

Bilateral Medial and Lateral Discoid Menisci: A Case Report.

Introduction: A discoid meniscus is a typical anatomical variation of the knee. There are several cases of either lateral or medial discoid menisci; however, their combination is rare. We describe a rare instance of bilateral discoid medial and lateral menisci. Case Report: A 14-year-old boy who developed left knee pain after twisting his knee at school was referred to our hospital. He had limited extension of -10°, lateral clicking, and pain on the McMurray test in the left knee and complained of slight clicks in the right knee. Magnetic resonance imaging results for both knees revealed discoid medial and lateral menisci. Surgery was performed on the symptomatic left knee. Arthroscopically, a Wrisberg-type discoid lateral meniscus and an incomplete-type medial discoid meniscus were confirmed. The symptomatic lateral meniscus was saucerized and sutured and only the asymptomatic medial meniscus was observed. The patient was doing well 24 months after surgery. Conclusion: We report a rare case of bilateral medial and lateral discoid menisci.

Pain detect questionnaire and pain catastrophizing scale affect gait pattern in patients with knee osteoarthritis.

PURPOSE: Although pain phenotype affects clinical score in patients with knee osteoarthritis (OA), little information has been available on the relationship between pain phenotype and gait analysis. The purpose was to investigate the relationship between pain phenotype and gait parameters.  METHODS: A total of 34 patients (24 females and 10 males) with end-stage medial compartmental knee OA participated. All the patients were evaluated based on pain detect questionnaire (PD-Q) and pain catastrophizing scale (PCS). They were divided into two categories: Group Low (PD-Q score ≤ 12) and Group High (PD-Q score > 12), PCS + (PCS ≥ 23) and PCS- (PCS < 23). Gait analysis was performed using three-dimensional motion analysis system. Statistical analysis was done to compare gait parameters between groups for each allocation of PD-Q or PCS, separately.  RESULTS: Peak vertical ground reaction forces in Group Low and High were 0.99 ± 0.054 and 0.82 ± 0.17, respectively (P = 0.015). Peak knee adduction moments in Group Low and High were 0.70 ± 0.19 and 0.39 ± 0.14, respectively (P = 0.0022). For PCS allocation, knee extension limitation during mid-stance during gait were significantly larger in PCS- (P = 0.038). CONCLUSIONS: Patients with high PD-Q score had atypical gait pattern with smaller peak vertical ground reaction force and knee adduction moment, compared to patients with low PD-Q score. Moreover, patient with low PCS had different gait pattern in extension limitation, compared to those with high PCS. PD-Q and PCS would affect gait pattern in patients with knee OA. LEVEL OF EVIDENCE: III.

A novel anteroposterior axis of the tibia for total knee arthroplasty: An upright weight-bearing computed tomography analysis.

BACKGROUND: The traditional anteroposterior (AP) axis (i.e., Akagi's line) has been widely used as the tibial component AP axis during total knee arthroplasty (TKA). However, this AP axis has been defined based on computed tomography (CT) in a non-weight-bearing supine position. In this study, AP axes of the tibial plateau from upright CT in weight-bearing and non-weight-bearing positions were determined and compared. METHODS: This study included 43 knees from 23 healthy volunteers. CT images were obtained in weight-bearing and non-weight-bearing standing positions using a 320-detector row upright CT scanner. The line perpendicular to surgical transepicondylar axis projected onto the tibia plateau was determined as the AP axis in upright weight-bearing and non-weight-bearing conditions. Angular differences between these two conditions were measured. RESULTS: The upright weight-bearing AP axis was positioned in a mean of 7.4 ± 4.3° of internal rotation relative to the traditional AP axis. Distance between the traditional and upright weight-bearing AP axis was 2.9 ± 1.6 mm at the edge of the tibial plateau. The upright non-weight-bearing AP axis was positioned in a mean of 3.5 ± 4.1° of internal rotation relative to the traditional AP axis. Mean angular difference between weight-bearing and non-weight-bearing conditions was 3.9 ± 4.1°. CONCLUSIONS: The upright weight-bearing AP axis was positioned in 7.4° of internal rotation relative to the traditional AP axis, showing one-seventh of the tibial tuberosity away from the medial border of the tibial tubercle, which represents a practical landmark for the tibial component AP axis during TKA.

Knee varus alters three-dimensional ankle alignment in standing- a study with upright computed tomography.

BACKGROUND: For knee osteoarthritis (OA) treatment, it is important to correct the lower limb alignment including the foot. However, in the upright position, lower limb alignment is generally assessed from the body surface or radiographs, and it is a challenge to capture the exact characteristics of three-dimensional lower limb alignment. The purpose of the study was to measure lower limb alignment in patients with knee OA using upright computed tomography (CT) and radiography, and to identify features of knee joint deformity. METHODS: A total of 45 limbs in 25 patients with knee OA were enrolled. The subjects underwent both upright CT and radiography for the whole lower limb in the standing position. The joint angles were calculated on both images. The degree of knee OA was classified according to Kellgren-Lawrence (KL) grade by referring to radiography, which is mainly based on the degree of articular cartilage loss and severity of osteophytes, and the characteristics or correlation between knee and ankle joint in each group was investigated. RESULTS: In KL-I, there was an association between varus of the knee joint and internal rotation of the talocrural joint (r = 0.76, P < 0.05). In KL-II, there was an association between varus of the knee joint and eversion of the subtalar joint (r = 0.63, P < 0.05) and talocrural joint (r = - 0.65, P < 0.05). In KL-III, there was an association between varus of the knee joint and internal rotation of the subtalar joint (r = - 0.62, P < 0.05), and in KL-IV, there was an association between varus of the knee joint and internal rotation of the subtalar joint (r = - 0.58, P < 0.05). CONCLUSIONS: The lower limb alignment of patients with knee OA in the standing position was found that as knee OA worsened, it became apparent that compensatory knee joint alignment depended on the ankle joint rather than the subtalar joint. The results may help in the rehabilitation of patients with knee OA, since the ankle joint alignment has a significant impact on the knee joint during coarse movements involving load.

Increase in tibial internal rotation due to weight-bearing is a key feature to diagnose early-stage knee osteoarthritis: a study with upright computed tomography.

BACKGROUND: The classification of knee osteoarthritis is an essential clinical issue, particularly in terms of diagnosing early knee osteoarthritis. However, the evaluation of three-dimensional limb alignment on two-dimensional radiographs is limited. This study evaluated the three-dimensional changes induced by weight-bearing in the alignments of lower limbs at various stages of knee osteoarthritis. METHODS: Forty five knees of 25 patients (69.9 ± 8.9 years) with knee OA were examined in the study. CT images of the entire leg were obtained in the supine and standing positions using conventional CT and 320-row detector upright CT, respectively. Next, the differences in the three-dimensional alignment of the entire leg in the supine and standing positions were obtained using 3D-3D surface registration technique, and those were compared for each Kellgren-Lawrence grade. RESULTS: Greater flexion, adduction, and tibial internal rotation were observed in the standing position, as opposed to the supine position. Kellgren-Lawrence grades 1 and 4 showed significant differences in flexion, adduction, and tibial internal rotation between two postures. Grades 2 and 4 showed significant differences in adduction, while grades 1 and 2, and 1 and 3 showed significant differences in tibial internal rotation between standing and supine positions. CONCLUSIONS: Weight-bearing makes greater the three-dimensional deformities in knees with osteoarthritis. Particularly, greater tibial internal rotation was observed in patients with grades 2 and 3 compared to those with grade 1. The greater tibial internal rotation due to weight-bearing is a key pathologic feature to detect early osteoarthritic change in knees undergoing osteoarthritis.

Four-dimensional computed tomographic analysis of screw home movement in patients with anterior cruciate ligament deficient knee - a 3D-3D registration technique.

OBJECTIVE: The tibia externally rotates to the femur during the last 20° of the knee extension motion. This kinematic phenomenon is well known as screw home movement (SHM). The purpose was to clarify the SHM in anterior cruciate ligament deficient (ACLD) knee using four-dimensional computed tomography (4DCT). MATERIALS AND METHODS: Six patients with a unilateral isolated ACLD knee participated. In the static position, CT scan of the both limbs of the femur and tibia were performed. Then, 4DCT was performed around knee. In the CT gantry, subjects were positioned in supine position with 45° of knee flexion on a triangle pillow and were asked to extend the knee to full extension within 10 s on each limb. The CT data were accumulated in digital imaging and communication in medicine (DICOM) data format. From the static CT and 4DCT DICOM data, three-dimensional surfaces of the knee joint were reconstructed. The whole tibia surface was matched into the partial tibia surface of that frame using 3D-3D registration technique. After the assessment of coordination system of the whole leg, knee flexion, abduction, and external rotation angle were calculated. RESULTS: Knee external rotation angle was significantly smaller on the ACLD side than on the contralateral unaffected side in 0-15° of knee flexion (P < 0.05 in 0, 5, 10, and 15 degrees), while the angle was similar during 15-60° of knee flexion. CONCLUSION: The absence of SHM in ACLD knee was detected using 3D-3D registration technique based on 4DCT.

Kinematically Aligned Total Knee Arthroplasty Using Medial Pivot Knee Prosthesis Enhances Medial Pivot Motion: A Comparative Kinematic Study With Mechanically Aligned Total Knee Arthroplasty.

BACKGROUND: Clinical outcomes of kinematically aligned total knee arthroplasty (KA-TKA) have been reported as comparable or superior to those of mechanically aligned TKA (MA-TKA). However, cruciate-retaining prostheses have mostly been used for KA-TKA. This study used medial pivot knee prostheses for KA-TKA, and knee kinematics after KA-TKA were assessed and compared with those after MA-TKA. METHODS: Thirteen knees in 9 patients undergoing primary TKA (8 KAs, 5 MAs) were subjected to two-dimensional (2D) to three-dimensional (3D) registration analysis at 1 year postoperatively. Each patient performed weight-bearing activities, and movements were recorded as intermittent digital radiographic images. Three-dimensional implant positions during activities were analyzed for anterior-posterior translation in the sagittal plane, condylar liftoff and mediolateral translation in the coronal plane, and femoral rotation in the axial plane. RESULTS: Posterior translation of the lateral femoral condyle from 0° to 100° was larger in KA-TKA than in MA-TKA (P = .006). The degrees of condylar liftoff and mediolateral translation were comparable between TKAs. Total external rotation of the femoral component relative to tibial component was significantly greater for KA-TKA (7.7 ± 5.2°) than for MA-TKA (1.3 ± 3.3°; P = .03). The kinematic path of the femoral component revealed greater medial pivoting motion in KA-TKA than in MA-TKA. CONCLUSIONS: KA-TKA using a medial pivot knee prosthesis successfully reproduced the medial pivot pattern and achieved larger femoral external rotation relative to the tibia than MA-TKA. KA-TKA was able to maximize the primary concept of the medial pivot knee prosthesis.

Factors related to large bone defects of bipolar lesions and a high number of instability episodes with anterior glenohumeral instability.

BACKGROUND: Significant bone defects are associated with poor clinical results after surgical stabilization in cases of glenohumeral instability. Although multiple factors are thought to adversely affect enlargement of bipolar bone loss and increased shoulder instability, these factors have not been sufficiently evaluated. The purpose of this study was to identify the factors related to greater bone defects and a higher number of instability episodes in patients with glenohumeral instability. METHODS: A total of 120 consecutive patients with symptomatic unilateral instability of the glenohumeral joint were retrospectively reviewed. Three-dimensional surface-rendered/registered models of bilateral glenoids and proximal humeri from computed tomography data were matched by software, and the volumes of bone defects identified in the glenoid and humeral head were assessed. After relationships between objective variables and explanatory variables were evaluated using bivariate analyses, factors related to large bone defects in the glenoid and humeral head and a high number of total instability episodes and self-irreducible dislocations greater than the respective 75th percentiles were evaluated using logistic regression analyses with significant variables on bivariate analyses. RESULTS: Larger humeral head defects (P < .001) and a higher number of total instability episodes (P = .032) were found to be factors related to large glenoid defects. On the other hand, male sex (P = .014), larger glenoid defects (P = .015), and larger number of self-irreducible dislocations (P = .027) were related to large humeral head bone defects. An increased number of total instability episodes was related to longer symptom duration (P = .001) and larger glenoid defects (P = .002), and an increased number of self-irreducible dislocations was related to larger humeral head defects (P = .007). CONCLUSIONS: Whereas this study showed that bipolar lesions affect the amount of bone defects reciprocally, factors related to greater bone defects differed between the glenoid and the humeral head. Glenoid defects were related to the number of total instability episodes, whereas humeral head defects were related to the number of self-irreducible dislocations.

Differences of tensile strength in knot tying technique between orthopaedic surgical instructors and trainees.

BACKGROUND: Knot tying technique is an extremely important basic skill for all surgeons. Clinically, knot slippage or suture breakage will lead to wound complications. Although some previous studies described the knot-tying technique of medical students or trainees, little information had been reported on the knot-tying technique of instructors. The objective of the preset study was to assess surgeons' manual knot tying techniques and to investigate the differences of tensile strength in knot tying technique between surgical instructors and trainees. METHODS: A total of 48 orthopaedic surgeons (postgraduate year: PGY 2-18) participated. Surgeons were requested to tie surgical knots manually using same suture material. They were divided into two groups based on each career; instructors and trainees. Although four open conventional knots with four throws were chosen and done with self-selected methods, knot tying practice to have the appropriate square knots was done as education only for trainees before the actual trial. The knots were placed over a 30 cm long custom made smooth polished surface with two cylindrical rods. All knots were tested for tensile strength using a tensiometer. The surgical loops were loaded until the knot slipped or the suture broke. The tensile strength of each individual knot was defined as the force (N) required to result in knot failure. Simultaneously, knot failure was evaluated based on knot slippage or suture rupture. In terms of tensile strength or knot failure, statistical comparison was performed between groups using two-tailed Mann-Whitney U test or Fisher exact probability test, respectively. RESULTS: Twenty-four instructors (PGY6-PGY18) and 24 trainees (PGY2-PGY5) were enrolled. Tensile strength was significantly greater in trainees (83.0 ± 27.7 N) than in instructors (49.9 ± 34.4 N, P = 0.0246). The ratio of slippage was significantly larger in instructors than in trainees (P < 0.001). Knot slippage (31.8 ± 17.7 N) was significantly worse than suture rupture (89.9 ± 22.2 N, P < 0.001) in tensile strength. CONCLUSIONS: Mean tensile strength of knots done by trainees after practice was judged to be greater than that done by instructors in the present study. Clinically, knot slippage can lead to wound dehiscence, compared to suture rupture.

Four-Dimensional CT Analysis Using Sequential 3D-3D Registration.

Four-dimensional computed tomography (4DCT) provides a series of volume data and visualizes joint motions. However, numerical analysis of 4DCT data remains difficult because segmentation in all volumetric frames is time-consuming. We aimed to analyze joint kinematics using a sequential 3D-3D registration technique to provide the kinematics of the moving bone with respect to the fixed bone semiautomatically using 4DCT DICOM data and existing software. Surface data of the source bones are reconstructed from 3DCT. The trimmed surface data are respectively matched with surface data from the first frame in 4DCT. These trimmed surfaces are sequentially matched until the last frame. These processes provide positional information for target bones in all frames of the 4DCT. Once the coordinate systems of the target bones are decided, translation and rotation angles between any two bones can be calculated. This 4DCT analysis offers advantages in kinematic analyses of complex structures such as carpal or tarsal bones. However, fast or large-scale motions cannot be traced because of motion artifacts.

Three-dimensional kinematic change of hindfoot during full weightbearing in standing: an analysis using upright computed tomography and 3D-3D surface registration.

BACKGROUND: Weightbearing of the hindfoot affects positional changes of the ankle joint and subtalar joint (ankle-joint complex [AJC]). However, it is difficult to assess the kinematic changes in the hindfoot in a natural full weightbearing condition using conventional CT or cone beam computed tomography (CT) due to limitations of acquiring foot images under a physiological weightbearing condition using those imaging modalities. Analysis of AJC kinematics using fluoroscopy and 2D-3D registration technique requires data on the number of steps and amount of time to build and match the bones. This study aimed to analyze the effect of full weightbearing on hindfoot motion when standing using upright CT and 3D-3D surface registration. METHODS: Forty-eight AJCs of 24 asymptomatic volunteers (13 women, 11 men) were examined under no weightbearing, 50% weightbearing, and single leg full weightbearing conditions while standing. The CT images were acquired from the distal femur to the whole foot using a 320-row upright CT scanner. The condition of each weightbearing stance was measured using a pressure mat. Bone-to-bone rotations of the talus relative to the tibia and calcaneus relative to the talus were evaluated using the surface registration technique. Image quality of the CT and intra- and interobserver reliabilities of the rotation angle were also evaluated. RESULTS: All CT images were excellent or good quality and the intra- and interobserver correlation coefficients for the angle were 0.996 and 0.995, respectively. The motion of the ankle joint and subtalar joint under 50% and 100% weightbearing were as follows (in degrees); the talus plantarflexed (5.1 ± 4.5 and 6.8 ± 4.8), inverted (1.3 ± 1.4 and 2.0 ± 1.6), and internally rotated (2.4 ± 4.2 and 4.3 ± 4.6) relative to the tibia, and the calcaneus dorsiflexed (2.8 ± 1.4 and 3.8 ± 1.7), everted (5.3 ± 2.6 and 8.0 ± 3.6), and externally rotated (3.0 ± 2.0 and 4.1 ± 2.4) relative to the talus, respectively. CONCLUSIONS: The effect of weightbearing was clearly identified using an upright CT and the 3D-3D registration technique. Three-dimensional kinematics under static full weightbearing were opposite between the ankle and subtalar joints on their respective axes.

Effect of body mass index on surgical times of lumbar laminoplasty and lower limb arthroplasties.

BACKGROUND: Obesity is an important factor affecting incidence and development of musculoskeletal degenerative changes. In addition, obese patients are considered less favorable surgical candidates for decompression surgery in degenerative lumbar spinal canal stenosis and lower limb arthroplasty. The purpose was to assess disease characteristics of lumbar spinal canal stenosis as well as lower limb osteoarthritis, and to investigate surgical times based on body mass index (BMI) in lumbar decompressive surgery and lower limb arthroplasties. METHODS: A total of 1161 patients with a diagnosis of lumbar canal stenosis (LCS), hip osteoarthritis (HOA) and knee osteoarthritis (KOA) were enrolled. The present investigation was conducted as a retrospective study using routinely collected data. All patients underwent primary decompressive surgery (laminoplasty: LAM) or lower limb arthroplasty (total hip arthroplasty: THA and total knee arthroplasty: TKA). All of the patients were divided into 3 groups based on BMI (kg/m2) (Group A: ≤ 24.9; Group B: 25-29.9; Group C: ≥ 30) within each disease category. To assess disease characteristics, age, gender, and BMI were evaluated for each disease category. Moreover, surgical times for LAM, THA and TKA were also assessed based on BMI classification. RESULTS: A total of 269, 470, and 422 patients were allocated to the HOA category, the KOA category, and the LCS category, respectively. The KOA category included the oldest patients and largest BMI, compared to the HOA and the LCS categories. Regarding gender difference, LCS was more common in males than in females, while opposite phenomenon was observed in the HOA and the KOA categories. The heaviest group (Group C) was significantly younger than Groups A or B in TKA and LAM. Surgical time was significantly longer in patients with overweight or obese patients than in those with normal weight in TKA and LAM, while BMI didn't affect the time in THA. CONCLUSIONS: Disease characteristics of the KOA category and the LCS category were notably affected by BMI, and surgical times in TKA and LAM were significantly longer for overweight or obese patients, whereas THA was less affected by BMI concerning disease characteristics and surgical time.

Clavicle fracture at the suture hole after acromioclavicular joint reconstruction using a suture-button: a case report.

BACKGROUND: Intraosseous suture-button devices have been used for acromioclavicular joint reconstruction due to its relative simplicity compared with other procedures. However, the complications of acromioclavicular joint reconstruction using a suture-button are not fully understood. Here, we describe a case of a clavicle fracture at the suture hole following acromioclavicular joint reconstruction using a suture-button and hook plate. CASE PRESENTATION: A 28-year-old man presented at our hospital after a fall from his bicycle. The patient had a history of acromioclavicular joint reconstruction with a suture-button and a hook plate for right acromioclavicular joint dislocation, seven months ago at another hospital. The hook plate had been removed four months ago, while X-ray radiography before removal had shown the widening of a suture hole. In the current fall from the bicycle, X-ray radiography revealed a clavicle fracture through the previous drill hole for suture-button. We removed the suture-button and performed an open reduction and internal fixation for the clavicle fracture. CONCLUSION: The present case indicated that a clavicle fracture at the suture hole, although rare, is one of the complications after an acromioclavicular joint reconstruction using a suture-button. This case suggested that drilling to the necessary minimum when making suture holes and paying attention to the widening of suture holes are important to prevent a postoperative clavicle fracture.

What are the important surgical factors affecting the wound healing after primary total knee arthroplasty?

BACKGROUND: Wound condition after primary total knee arthroplasty (TKA) is an important issue to avoid any postoperative adverse events. Our purpose was to investigate and to clarify the important surgical factors affecting wound score after TKA. METHODS: A total of 139 knees in 128 patients (mean 73 years) without severe comorbidity were enrolled in the present study. All primary unilateral or bilateral TKAs were done using the same skin incision line, measured resection technique, and wound closure technique using unidirectional barbed suture. In terms of the wound healing, Hollander Wound Evaluation Score (HWES) was assessed on postoperative day 14. We performed multiple regression analysis using stepwise method to identify the factors affecting HWES. Variables considered in the analysis were age, sex, body mass index (kg/m(2)), HbA1C (%), femorotibial angle (degrees) on plain radiographs, intraoperative patella eversion during the cutting phase of the femur and the tibia in knee flexion, intraoperative anterior translation of the tibia, patella resurfacing, surgical time (min), tourniquet time (min), length of skin incision (cm), postoperative drainage (ml), patellar height on postoperative lateral radiographs, and HWES. HWES was treated as a dependent variable, and others were as independent variables. RESULTS: The average HWES was 5.0 ± 0.8 point. According to stepwise forward regression test, patella eversion during the cutting phase of the femur and the tibia in knee flexion and anterior translation of the tibia were entered in this model, while other factors were not entered. Standardized partial regression coefficient was as follows: 0.57 in anterior translation of the tibia and 0.38 in patella eversion. CONCLUSIONS: Fortunately, in the present study using the unidirectional barbed suture, major wound healing problem did not occur. As to the surgical technique, intraoperative patella eversion and anterior translation of the tibia should be avoided for quality cosmesis in primary TKA.

What are the important manoeuvres for beginners to minimize surgical time in primary total knee arthroplasty?

PURPOSE: It was hypothesized that surgical time of beginners would be much longer than that of experts. Our purpose was to investigate and clarify the important manoeuvres for beginners to minimize surgical time in primary total knee arthroplasty (TKA) as a multicentre study. METHODS: A total of 300 knees in 248 patients (averaged 74.6 years) were enrolled. All TKAs were done using the same instruments and the same measured resection technique at 14 facilities by 25 orthopaedic surgeons. Surgeons were divided into three surgeon groups (four experts, nine medium-volume surgeons and 12 beginners). The surgical technique was divided into five phases. Detailed surgical time and ratio of the time in each phase to overall surgical time were recorded and compared among the groups in each phase. A total of 62, 119, and 119 TKAs were done by beginners, medium-volume surgeons, and experts, respectively. RESULTS: Significant differences in surgical time among the groups were seen in each phase. Concerning the ratio of the time, experts and medium-volume surgeons seemed cautious in fixation of the permanent component compared to other phases. Interestingly, even in ratio, beginners and medium-volume surgeons took more time in exposure of soft tissue compared to experts. (0.14 in beginners, 0.13 in medium-volume surgeons, 0.11 in experts, P < 0.05). CONCLUSION: Beginners took more time in exposure and closure of soft tissue compared to experts. Improvement in basic technique is essential to minimize surgical time among beginners. First of all, surgical instructors should teach basic techniques in primary TKA for beginners. LEVEL OF EVIDENCE: Therapeutic studies, Level IV.