Keiichiro Oura

Postoperative accuracy analysis of three-dimensional corrective osteotomy for cubitus varus deformity with a custom-made surgical guide based on computer simulation

BACKGROUND For correction of cubitus varus deformity resulting from supracondylar fracture of the humerus, we developed an operative method with use of a custom-made surgical guide, designed on the basis of 3-dimensional (3D) computer simulation with computed tomography data. The purpose of this study was to investigate the postoperative accuracy of this system in clinical cases. METHODS Subjects included 17 consecutive patients (13 males and 4 females) with cubitus varus deformity after supracondylar fracture. Patients underwent 3D corrective osteotomy with use of a custom-made surgical guide. Postoperative computed tomography scan was performed after bone union diagnosis on plain radiographs, and postoperative 3D bone models were compared with preoperative simulation by surface registration technique. In addition, we evaluated radiographic parameters (humerus-elbow-wrist angle and tilting angle) and range of elbow motion at the most recent follow-up. RESULTS Mean errors in 3D corrective osteotomy were 0.6° ± 0.7° in varus-valgus rotation, 0.8° ± 1.3° in flexion-extension rotation, 2.9° ± 2.8° in internal-external rotation, 1.7 ± 1.8 mm in anterior-posterior translation, 1.3 ± 1.8 mm in lateral-medial translation, and 7.1 ± 6.3 mm in proximal-distal translation. The mean humerus-elbow-wrist angle on plain radiographs of the affected side was 15° in varus before surgery and improved to 6° in valgus after surgery. The mean tilting angle of the affected side was 31° before surgery and improved to 40° after surgery. CONCLUSION The 3D correction of cubitus varus deformity was performed accurately within the allowable error limits.

Three-dimensional corrective osteotomy using a patient-specific osteotomy guide and bone plate based on a computer simulation system: accuracy analysis in a cadaver study

The accuracy of three‐dimensional (3‐D) corrective osteotomy using a patient‐specific osteotomy guide and bone plate based on computer simulation was investigated.

Volar morphology of the distal radius in axial planes: A quantitative analysis

To investigate the cause of rupture of the flexor pollicis longus (FPL) after volar plate fixation of distal radius fractures, previous studies have examined the shape of the distal radius in the sagittal plane or in the lateral view. However, there are no reports on the anatomical shape of the volar surface concavity of the distal radius in the axial plane. We hypothesized that this concavity might contribute to the mismatch between the plate and the surface of the radius. To test this hypothesis, we constructed three‐dimensional models of the radius and FPL based on computed tomography scans of 70 normal forearms. We analyzed axial cross‐sectional views with 2 mm intervals. In all cases, the volar surface of the distal radius was concave in the axial plane. The concavity depth was maximum at 6 mm proximal to the palmar edge of the lunate fossa and progressively decreased toward the proximal radius. FPL was closest to the radius at 2 mm proximal to the palmar edge of the lunate fossa. The volar surface of the distal radius was externally rotated from proximal to distal. These results may help to develop new implants which fit better to the radius and decrease tendon irritation.

Prediction of forearm bone shape based on partial least squares regression from partial shape

Computer‐assisted corrective osteotomy using a mirror image of the normal contralateral shape as reference is increasingly used. Instead, we propose to use the shape predicted by statistical learning to deal with cases demonstrating bilateral abnormality, such as bilateral trauma, congenital disease, and metabolic disease.

Corrective osteotomy for hyperextended elbow with limited flexion due to supracondylar fracture malunion

BACKGROUND Extension deformity of the distal humerus after a malunited supracondylar fracture can restrict elbow flexion. Here we report a computer-assisted operative procedure and review the results of clinical cases in which corrective surgery was performed. METHODS The medical records of the patients who underwent corrective osteotomy for hyperextended elbow malunion of the distal humerus with limited elbow flexion (flexion angle ≤100°) were reviewed retrospectively. Osteotomy was performed using patient-specific instruments designed based on preoperative 3-dimensional computer simulation. RESULTS Three patients, a 55-year-old woman and two 12-year-old boys, met the inclusion criteria. The angles of hyperextension of the affected distal humerus were 29°, 29°, and 25°, respectively. The range of flexion/extension of the elbow motion in the first patient improved from 95°/25° preoperatively to 140°/-10° postoperatively, in the second patient from 100°/20° to 145°/5°, and in the third patient from 80°/25° to 140°/10°. Bone union was achieved in all patients. There were no major complications. The corrective operations not only improved elbow flexion but also increased the total range of motion in the elbow by rebuilding the anterior curve of the distal humerus. CONCLUSIONS Correction of the extension deformity of the distal humerus after a malunited supracondylar fracture is a reasonable option for patients older than 10 years with restricted elbow flexion. Preoperative computer simulation and the use of patient-specific instruments can be a useful alternative that enables accurate deformity correction and improves the total range of motion.

Anconeus Muscle-Pedicle Bone Graft With Periosteal Coverage for Osteochondritis Dissecans of the Humeral Capitellum

Background: Treatment of advanced osteochondritis dissecans (OCD) of the capitellum is controversial, especially in moderate-sized lesions. Purpose: To establish a treatment algorithm for capitellum OCD, we tried to determine the utility of and problems associated with anconeus muscle-pedicle bone graft with periosteal coverage (ABGP) for the treatment of moderate-sized articular OCD defects of the capitellum. Study Design: Case series; Level of evidence, 4. Methods: According to our protocol for elbow OCD, 16 patients (15 males, 1 female; age range, 12-17 years; mean age, 14.4 years) with a moderate-sized OCD lesion of the humeral capitellum were treated with ABGP. All patients had a full-thickness, unstable OCD lesion that was 10 to 15 mm in diameter. Clinical results and postoperative images, including radiographs and magnetic resonance imaging (MRI), were evaluated at a mean follow-up of 31 months (range, 24-66 months). Results: All but 1 patient had functional improvement after the procedure and returned to previous sporting activities within 6 months. One female patient needed 1 year for functional recovery due to development of postoperative chronic regional pain syndrome (CRPS). Two patients required additional surgery, including shaving of the protruding cartilage, and they returned to their previous level of activity. Mean arc of range of flexion-extension motion was 117° preoperatively and 129° at follow-up (P = .031). Mean elbow function as assessed with the clinical rating system of Timmerman and Andrews was 136 preoperatively and 186 at follow-up (P = .00012). Bony union of the graft as demonstrated by trabecular bone bridging on radiography was obtained within 3 months in all patients. Postoperative MRI was examined for 14 patients at 6 to 12 months after the procedure; the MRIs showed near-normal articular surface integrity in 9 of the 14 patients (64%) and underlying bony structure in 10 of the 14 patients (71%). Conclusion: Improvement after ABGP was obtained within 6 months in all except 1 patient, who developed CRPS. Postoperative radiography and MRI revealed near-normal articular surface integrity or underlying bony structure. This procedure is useful as a surgical option for a moderate-sized articular OCD lesion in the elbow.

Muscle-pedicle Bone Grafting With Periosteum Coverage for Osteochondritis Dissecans A Case Series

Objective/Hypothesis: There are several treatment options for osteochondritis dissecans (OCD) of humeral capitellum. In a previous study, we reported muscle-pedicle bone grafting with periosteum coverage for OCD. The purpose of the current study was to review the results of this surgery. Materials and Methods: Eight patients who underwent muscle-pedicle bone grafting with periosteum coverage for OCD between 2011 and 2015 were reviewed retrospectively. The surgical technique is as follows: Unstable OCD lesion was debrided. Cuboid bone graft with the anconeus muscle pedicle was harvested from the posterior side of the capitellum. When obtaining the bone graft, extra periosteum was also obtained and kept attached to the bone graft. Bone tunnel was created from the harvested site to the debrided site. The bone graft was covered with the attached periosteum and inserted through the tunnel. The periosteum edge of the inserted graft was sutured with cartilage around the debrided site. The patients were placed in a long-arm splint for 2 to 3 weeks, followed by gentle mobilization. Gradual return-to-play program was started after radiographic signs of healing. Patients were usually allowed to recover to full sports activity around 6 months after surgery. The medical records of the 8 patients were reviewed for the following information: (1) sports and position; (2) preoperative and final range of motion; (3) duration from surgery to return to sports activity; (4) radiographic outcomes, including size of OCD lesion, grafted bone union, and enlargement of the radial head; and (5) complications. Enlargement of the radial head was defined as an increase in the diameter of more than 20% between preoperative and final anteroposterior radiographs. Results: Eight elbows in 8 patients (7 male and 1 female) with a mean age of 14 years (range, 12-16 years) underwent muscle-pedicle bone grafting with periosteum coverage during the period. Mean follow-up duration was 19 months (range, 6-34 months). Sports, the patients performed, include baseball (7 patients) and tennis (1 patient). In the 7 baseball players, 2 patients were pitchers, 1 was a catcher, 3 were infielders, and 1 was an outfielder. Preoperative range of flexion and extension were 129.4 ± 6.8° (mean ± SD) and −4.4 ± 8.6°, respectively. Final range of flexion and extension were 131.9 ± 11.9° and −2.5 ± 12.8°, respectively. There were no significant difference in preoperative and final range of motion. Patients returned to sports activity in 5 to 7 months after surgery. Seven of 8 patients returned to the same sports level, but 1 patient returned to other sports. The mean anteroposterior and transverse diameters of the cartilage defect were 12.0 (range, 8-14 mm) and 10.6 mm (range, 7-13 mm), respectively. Grafted bone union was achieved in all patients. Enlargement of the radial head was observed in 2 patients. Conclusions: Muscle-pedicle bone grafting with periosteum coverage was one of the acceptable treatment options for OCD of humeral capitellum. Reconstruction of articular defect in OCD was possible with minimum donor site morbidity.

Surgical Treatment Protocol for the Advanced Articular Lesion of Osteochondritis Dissecans of the Elbow

Hypothesis: Advanced lesion of osteochondritis dissecans (OCD) of the elbow should be treated surgically by the protocol “arthroscopic debridement with or without reconstruction according to the lesion size.” Materials and Methods: In total, 131 advanced OCD patients (International Cartilage Research Society [ICRS] OCD III or IV) were treated and followed more than 18 months (18-140 with mean of 36 months). Most of the patients were young boys such as baseball players, gymnasts, boxers, and judo athletes. The elbow OCD lesions were evaluated by preoperative x-ray, computed tomography (CT), or magnetic resonance imaging (MRI), and classified into 3 types by lesion size: small (articular lesion diameter [ALD] smaller than 10 mm), medium (ALD 10-15 mm), and large (ALD larger than 15 mm). For a small lesion, it was shaved arthroscopically (AS, n = 32). For a medium lesion, it was reconstructed by a local anconeus muscle–pedicled bone graft (BG) covered with periosteum flap (n = 16). For a large lesion, it was completely shaved and reconstructed by osteochondral autograft transplantation (OAT) from the patient’s knee (n = 16) or reconstructed by cylindrical costal-rib osteochondral autograft (CCOA, n = 67). Totally, 159 patients were operated in 1998 to 2014 and 131 were enrolled in this follow-up study (follow-up rate, 82.4%). Clinical findings (pain, range of motion [ROM], and physical activity) were reviewed. Timmerman and Andrews score was evaluated before and after surgery. Results: Overall Findings—Preoperative symptoms were pain, elbow catching in their activities, and limitation of motion. Their sports activities were limited. Pain and catching were improved after surgery. ROM (flexion/extension) was 126/–14 preoperatively and improved to 134/–4 at final follow-up. More than 90% of the patients returned to their former activities. Timmerman and Andrews score was 130 preoperatively and improved to 186 at final follow-up. Each procedure showed equally good end results (ROM: preoperative and at follow-up, 125/–9 improved to 132/–4 in AS, 128/–13 improved to 135/1 in BG, 125/–11 improved to 134/–5 in OAT, and 126/–17 improved to 134/–4 in CCOA; Timmerman and Andrews: 144 improved to 185 in AS, 141 improved to 193 in BG, 134 improved to 180 in OAT, and 121 improved to 186 in CCOA). Twenty-one additional minor surgeries such as hardware removal or arthroscopic removal of free bodies were performed in 21 cases in the follow-up. Conclusions: Complete resection of the damaged articular lesion is recommended for the advanced OCD of the elbow. For a large articular lesion, several types of reconstruction were possible. This protocol will serve good functional recovery to some extent for the damaged young athletes’ elbow.