A1 pulley stretching treats trigger finger: A1 pulley luminal region under digital flexor tendon traction.

BACKGROUND: A1 pulley stretching is recognized as a clinically beneficial treatment for trigger finger. It is thought to lead to an increase in the cross-sectional area of the A1 pulley luminal region, thus improving trigger finger symptoms. The purpose of the present study was thus to evaluate the resultant forces during stretching that increase the CSA of the A1 pulley luminal region using fresh-frozen cadavers. METHODS: Using seven fingers from three fresh-frozen cadavers to replicate A1 pulley stretching, we investigated the resultant forces during stretching that increase the cross-sectional area of the A1 pulley luminal region. The traction forces of the flexor digitorum profundus tendons were increased in steps to 150 N, and the cross-sectional area and height of the A1 pulley luminal region were measured using ultrasonography. FINDINGS: The cross-sectional area of the A1 pulley luminal region increased with step-wise increases in the flexor digitorum profundus traction. On average, the cross-sectional area and height of the A1 pulley luminal region showed increases of 31.4% and 43.6%, respectively, compared to the unloaded condition. INTERPRETATION: These results confirmed that A1 pulley stretching increases the cross-sectional area of the A1 pulley luminal region. A1 pulley stretching has the potential to reduce the severity of trigger finger in patients facing surgery.

Smith's fracture generally occurs after falling on the palm of the hand.

Orthopedic trauma surgeons often encounter Smith's fracture in patients who report that they have fallen on the palms of their hands. The aim of this study was to clarify the pathogenesis of Smith's fracture in basic clinical aspects. First, a survey was conducted for investigating the mechanism of injury and arm position at the time of injury among patients with Smith's fractures who consulted at our outpatient clinic. Second, we created three-dimensional finite element models (FEMs) to predict the influence of arm position on the type of injury resulting from a fall. These predictions were then used in ten freshly frozen cadavers to provide experimental proof of Smith's fractures resulting from the impact on the palmar side. Twenty-six patients (5 males and 21 females) with Smith's fractures were enrolled in this study. Injury resulting from a fall on the palm of the hand, the dorsum, or ulno-dorsum of the hand, and fisting handle was observed in 16 cases (61%), 3 cases (12%), and 1 case (4%), respectively. Six patients were uncertain of their arm position at the time of injury. FEM analysis showed that Smith's fractures occurred when the angle between the long axis of the forearm and the ground was 30°-45° in the sagittal plane and 75°-90° in the coronal plane. Smith's fractures occurred in 7 of 10 wrists in the experimental study, whereas no Colles' fractures were observed. This study demonstrated that Smith's fracture results from falling on the palm of the hand. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:2435-2441, 2017.

Accuracy of Pedicle Screw Placement in Scoliosis Surgery: A Comparison between Conventional Computed Tomography-Based and O-Arm-Based Navigation Techniques.

STUDY DESIGN: Retrospective study. PURPOSE: We compared the accuracy of O-arm-based navigation with computed tomography (CT)-based navigation in scoliotic surgery. OVERVIEW OF LITERATURE: No previous reports comparing the results of O-arm-based navigation with conventional CT-based navigation in scoliotic surgery have been published. METHODS: A total of 222 pedicle screws were implanted in 29 patients using CT-based navigation (group C) and 416 screws were implanted in 32 patients using O-arm-based navigation (group O). Postoperative CT was performed to assess the screw accuracy, using the established Neo classification (grade 0: no perforation, grade 1: perforation <2 mm, grade 2: perforation ≥2 and <4, and grade 3: perforation ≥4 mm). RESULTS: In group C, 188 (84.7%) of the 222 pedicle screw placements were categorized as grade 0, 23 (10.4%) were grade 1, 11 (5.0%) were grade 2, and 0 were grade 3. In group O, 351 (84.4%) of the 416 pedicle screw placements were categorized as grade 0, 52 (12.5%) were grade 1, 13 (3.1%) were grade 2, and 0 were grade 3. Statistical analysis showed no significant difference in the prevalence of grade 2.3 perforations between groups C and O. The time to position one screw, including registration, was 10.9±3.2 minutes in group C, but was significantly decreased to 5.4±1.1 minutes in group O. CONCLUSIONS: O-arm-based navigation facilitates pedicle screw insertion as accurately as conventional CT-based navigation. The use of O-arm-based navigation successfully reduced the time, demonstrating advantages in the safety and accuracy of pedicle screw placement for scoliotic surgery.

Anterolateral Corrective Lumbar Corpectomy and Interbody Fusion by Using Extended Screw Fixation without Posterior Instrumentation for Posttraumatic Kyphosis.

A 26-year-old paraplegic schizophrenic Japanese woman suffered from severe kyphosis and back pain derived from lumbar burst fractures caused by jumping. She had already undergone resection of the L1 and L2 spinous processes for sharp angular kyphosis, but she still had severe kyphosis and back pain at the L1 and L2. Radiographical examination revealed fused anterior columns at L1 and L2 with severe local kyphosis and a significantly decreased percutaneous distance in the back. The patient underwent anterior instrumented bony resection including an L2 vertebral osteotomy: bilateral L2-L3 facetectomy and partial posterior osteotomy of the L2 vertebrae via a posterior approach followed by an anterior corpectomy of the L2 vertebrae and insertion of a cylindrical cage. No posterior instrumentation was used owing to the presence of atrophied paraspinal soft tissues. Lumbar interbody fusion was performed with vertebral body screws extending from T12 to L4 and corresponding anterior distension and posterior compression. The procedure corrected the kyphosis by 15° and enhanced local stability. Postsurgical visual analogue scale improved from 9.0 to 2.0 and Oswestry Disability Index from 40 to 17.8, respectively. In conclusion, we have demonstrated that anterolateral interbody fusion using extended fixation can compensate for posterior corrective surgery.