Three-dimensional corrective osteotomy for cubitus varus deformity using patient-matched instruments.

Background: Various methods of two or three-dimensional (3D) corrective osteotomy for cubitus varus deformity have been reported. However, whether 3D correction of cubitus varus deformity is necessary is controversial because of technical difficulties and surgical complications. This study introduced 3D simulations and printing technology for corrective osteotomy against cubitus varus deformities. Moreover, recent studies on the application of these technologies were reviewed. Methods: The amount of 3D deformity was calculated based on the difference in 3D shape between the affected side and the contralateral normal side. Patient-matched instruments were created to perform the actual surgery as simulated. Further, a 3D corrective osteotomy was performed using patient-matched instruments for cubitus varus deformity in pediatric and adolescent patients. The humerus-elbow-wrist angle, tilting angle, and elbow ranges of motion were evaluated. Results: Humerus-elbow-wrist angle and tilting angle were corrected from -21° to 14° and from 30° to 43°, respectively, in the pediatric patient and from -18° to 10° and from 20° to 40°, respectively, in the adolescent patient. The elbow flexion and extension angles changed from 130° to 140° and from 20° to 10°, respectively, in the pediatric patient and from 120° to 130° and from 15° to 0°, respectively, in the adolescent patient. Conclusion: The 3D computer simulations and the use of patient-matched instruments for cubitus varus deformity are reliable and can facilitate an accurate and safe correction. These technologies can simplify the complexity of 3D surgical procedures and contribute to the standardization of treatment for cubitus varus deformity.

Cubitus varus deformity following paediatric supracondylar humeral fracture remodelling predominantly in the sagittal direction: A three-dimensional analysis of eighty-six cases.

PURPOSE: Three-dimensional (3D) capacity for remodelling in cubitus varus deformity (CVD) after paediatric supracondylar humeral fractures (PSHFs) remains unelucidated. This study investigated remodelling patterns after PSHFs by examining 3D deformity distribution over time after injury. METHODS: Computed tomography (CT) data of 86 patients with CVD after PSHFs were analysed. The 3D deformity angles in the sagittal, coronal, and axial directions were assessed and correlated with the duration between the age at injury and CT evaluation. For the subgroup analysis, we performed the same correlation analysis in a younger (< 8 years old) and an older group (≥ 8 years old); we categorized the duration into early (< 2 years), middle (≥ 2 to < 5 years), and late periods (≥ 5 years) and compared the deformity angles of each direction among the three groups. RESULTS: Sagittal deformity showed a moderate correlation with the duration of deformity (r = -0.54; P < 0.001), while coronal and axial deformities showed a negligible correlation. Sagittal deformity showed moderate correlations with the duration in the younger group (r = -0.62; P < 0.001) and weak correlations in the older group (r = -0.37; P = 0.091). In the sagittal direction, the deformity angle in the early period was significantly larger than those in the mid and late periods (P < 0.001). However, there were no significant differences among the three groups in the coronal and axial directions. CONCLUSION: Sagittal deformities in CVDs are capable of remodelling, especially in the early period and at a younger age, whereas coronal and axial deformities are less likely to undergo remodelling.

Reproduction of forearm rotation dynamic using intensity-based biplane 2D-3D registration matching method.

This study aimed to reproduce and analyse the in vivo dynamic rotational motion of the forearm and to clarify forearm motion involvement and the anatomical function of the interosseous membrane (IOM). The dynamic forearm rotational motion of the radius and ulna was analysed in vivo using a novel image-matching method based on fluoroscopic and computed tomography images for intensity-based biplane two-dimensional-three-dimensional registration. Twenty upper limbs from 10 healthy volunteers were included in this study. The mean range of forearm rotation was 150 ± 26° for dominant hands and 151 ± 18° for non-dominant hands, with no significant difference observed between the two. The radius was most proximal to the maximum pronation relative to the ulna, moved distally toward 60% of the rotation range from maximum pronation, and again proximally toward supination. The mean axial translation of the radius relative to the ulna during forearm rotation was 1.8 ± 0.8 and 1.8 ± 0.9 mm for dominant and non-dominant hands, respectively. The lengths of the IOM components, excluding the central band (CB), changed rotation. The transverse CB length was maximal at approximately 50% of the rotation range from maximum pronation. Summarily, this study describes a detailed method for evaluating in vivo dynamic forearm motion and provides valuable insights into forearm kinematics and IOM function.

Acceptable range of forearm deformity derived from relation to three-dimensional analysis and clinical impairments.

This study aimed to investigate deformity patterns that cause clinical impairments and determine the acceptable range of deformity in the treatment of forearm diaphyseal fractures. A three-dimensional (3D) deformity analysis based on computed bone models was performed on 39 patients with malunited diaphyseal both-bone forearm fractures to investigate the 3D deformity patterns of the radius and ulna at the fracture location and the relationship between 3D deformity and clinical impairments. Clinical impairments were evaluated using forearm motion deficit. Cutoff values of forearm deformities were calculated by performing receiver operating characteristic analysis using the deformity angle and the limited forearm rotation range of motion (less than 50° of pronation or supination) resulting in activities of daily living (ADL) impairment as variables. The extension, varus, and pronation deformities most commonly occurred in the radius, whereas the extension deformity was commonly observed in the ulna. A positive correlation was observed between pronation deficit and extension deformity of the radius (R = 0.41) and between supination deficit and pronation deformity of the ulna (R = 0.44). In contrast, a negative correlation was observed between pronation deficit and pronation deformity of the radius (R = -0.44) and between pronation deficit and pronation deformity of the ulna (R = -0.51). To minimize ADL impairment, radial extension deformity should be <18.4°, radial rotation deformity <12.8°, and ulnar rotation deformity <16.6°. The deformities in the sagittal and axial planes of the radius and in the axial plane of the ulna were responsible for the limited forearm rotation.

Quantitative Analysis for the Change in Lengths of the Radius and Ulna in Missed Bado Type I Monteggia Fracture.

BACKGROUND: In missed Monteggia fracture (MMF) cases, ulnar angulation and lengthening by osteotomy are required to reduce the dislocated radial head. This study aimed to clarify the abnormal discrepancy in length between the radius and ulna in MMF. We tested the hypothesis that the increase in the abnormal discrepancy in length between the radius and ulna relates with the duration of radial head dislocation. METHODS: In total, 24 patients with MMF were studied and classified into 2 groups, according to the duration of radial head dislocation, including the early group (n=9, within 3 y) and the long-standing group (n=15, older than 3 y). The lengths of the radius (Lr) and ulna (Lu) were measured. The difference in length between the ulna and radius (DL=Lu-Lr) was calculated on both the affected (DLaff) and normal (DLnor) sides. DLnor-DLaff, which represented an abnormal discrepancy in both bones, was analyzed for correlation with the duration of radial head dislocation and the age at initial injury. RESULTS: The affected and normal sides had no differences in the Lr of both the groups and in the Lu of the early group. However, in the long-standing group, Lu was significantly smaller in the affected side than in the normal side (P=0.001). In the long-standing group, DLaff was significantly smaller, owing to decreased length of the ulna, than DLnor (P=0.003). The DLnor-DLaff was positively correlated with the duration of radial head dislocation and was negatively correlated with the age at injury. CONCLUSIONS: In chronic MMF cases, the length of the ulna was shorter in the affected side than in the normal side. Therefore, ulnar lengthening is necessary to resolve this abnormal discrepancy and reduce the radial head. Because excessive ulnar lengthening has risks of postoperative complications, one of the surgical options is gradual ulnar lengthening or shortening osteotomy of the radius. LEVEL OF EVIDENCE: Level III-Prognosis study.

Loop Length Change of an Adjustable-Length Femoral Cortical Suspension Device in Anatomic Rectangular Tunnel Anterior Cruciate Ligament Reconstruction With a Bone-Patellar Tendon-Bone Graft and Associated Clinical Outcomes.

PURPOSE: To evaluate loop length changes of an adjustable femoral cortical suspensory fixation device and assess the clinical results after anatomic rectangular tunnel anterior cruciate ligament (ART-ACL) reconstruction with a bone-tendon-bone (BTB) graft. METHODS: The study included 50 patients who underwent ART-ACL reconstruction with a BTB graft fixed using the adjustable-length device BTB TightRope for femoral fixation between July 2013 and December 2014. Computed tomography examinations were performed at 1 and 12 weeks after the surgery. Loop length was measured in the reconstructed plane just parallel to the femoral tunnel, including the bone plug and the button. Measurement was performed thrice, and the mean value was used. Loop length change was defined as the difference in loop length between 1 and 12 weeks after the surgery. A paired t test was conducted with the effect size for statistical analysis. At 2 years postoperatively, clinical evaluations, including subjective and objective assessments, were performed. RESULTS: The mean loop lengths at 1 and 12 weeks were 25.77 ± 3.88 mm and 25.81 ± 3.89 mm, respectively, with a significant difference (P = .01). However, the effect size was 0.01, suggesting that the difference was not meaningful. The mean individual loop length change was 0.04 ± 0.13 mm. All individual loop length changes were within the measurement error range. At 2 years postoperatively, 49 patients (98%) were graded as normal or nearly normal according to the International Knee Documentation Committee form. The mean side-to-side difference in anterior laxity at manual maximum force was 0.2 ± 0.5 mm. CONCLUSIONS: The loop length change of an adjustable-length femoral cortical suspension device was negligible after ART-ACL reconstruction with a BTB graft. This ART-ACL reconstruction with a BTB graft using an adjustable-length device could safely provide sufficient stability to the operated knee. LEVEL OF EVIDENCE: Level Ⅳ, therapeutic case series.