Preoperative radius head dislocation affects forearm rotation after mobilization of congenital radioulnar synostosis.

BACKGROUND: The present study was carried out to answer three questions: 1) How much forearm rotation can be expected after mobilization of congenital radioulnar synostosis (CRUS)? 2) Does preoperative radius head dislocation affect forearm rotation after mobilization? 3) What factors other than radius head dislocation affect postoperative forearm rotation? METHODS: We performed mobilization of CRUS with a free vascularized fascio-fat graft and a radius osteotomy (Kanaya's procedure) on 26 forearms of 25 patients. The age at the surgery ranged from 5.3 to 13.4 years. The follow-up duration ranged 24-111 months. We classified CRUS into 3 groups according to the dislocation of the radius head: posterior dislocation (N = 13), anterior dislocation (N = 9) and no dislocation (N = 4). Since major complaints of patients and parents were poor forearm rotation and lack of supination, they were evaluated separately. RESULTS: Mean preoperative forearm ankylosis angle was 34.8° (range; neutral to 90° pronation). Preoperative pronation ankylosis angle was higher in the posterior dislocation group (mean 55.3°) than the anterior dislocation (mean 11.6°) and no dislocation groups (mean 5.0°). There was no re-ankylosis after mobilization and the mean postoperative active range of motion (ROM) was 86.5°. The mean active ROM was 75.7° in the posterior dislocation group, 96.1° in anterior dislocation group and 100.0° in no dislocation group. The mean active supination was 6.9, 33.9 and 47.5° respectively. The posterior dislocation group showed less ROM and less supination than other groups. Preoperative pronation ankylosis angle showed negative correlation with postoperative ROM (ρ = - 0.59) and postoperative supination (ρ = - 0.73). CONCLUSION: The mean postoperative active ROM of this mobilization was 86.5°. Posterior dislocation group showed higher pronation ankylosis angle preoperatively, and less postoperative ROM and less supination than anterior and no dislocation groups. Preoperative pronation ankylosis angle showed negative correlation with postoperative ROM and supination.

Bone Morphology in Ulnar Impaction Syndrome: A Radiographic Evaluation.

Background: Positive ulnar variance (UV) may be associated with a higher incidence of ulnar impaction syndrome (UIS). However, neutral and/or negative UV has also been associated with the development of UIS; therefore, other risk factors may be involved. The purpose of this study was to compare radiological bone morphology in patients with UIS and asymptomatic controls. Methods: Between 2009 and 2018, posteroanterior wrist radiographs of 47 wrists in 45 patients diagnosed with UIS were compared with those of 163 wrists in 93 asymptomatic patients from the control group. The following parameters were obtained: ulnar variance (UV); ulnar head top-fovea distance (UTFD); capitate-triquetrum distance (CTD); radio-lunate distance (RLD) and lunate coverage ratio (LCR). The morphology of the lunate was classified based on the absence (type I) or presence (type II) of a medial facet that articulates with the hamate. The radiographic parameters and lunate types were compared between the two groups. We then divided the groups into two subgroups: the positive UV subgroup and the neutral/negative UV subgroup. In each subgroup, the radiographic parameters and lunate types were compared between the UIS and control groups. Results: In the UIS group, the UV and UTFD were significantly increased compared to those in the control group. The proportion of type II lunates was significantly higher in the UIS group than in the control group. In addition, the type II lunate was more common in the UIS group in both the positive UV and negative UV groups. Conclusions: Our study suggests that in addition to positive UV, ulnar head morphology with an increased UTFD and type II lunate morphology may be associated with the development of ulnar impaction syndrome. Level of Evidence: Level III (Diagnostic).

Veno-accompanying artery fasciocutaneous flaps following wide excision of soft tissue tumors in the lower legs.

BACKGROUND: Soft tissue defects following wide excision of malignant soft tissue tumors (STTs) are sometimes too large for primary closure, especially in the lower legs where available soft tissue is limited. This study aimed to determine the clinical outcomes of reconstruction of a defect after wide excision of an STT with a veno-accompanying artery fasciocutaneous (VAF) flap in the lower leg. METHODS: This study comprised 9 patients with malignant STTs who had undergone reconstructive surgeries using VAF flaps after wide excisions, between October 2010 and September 2017. We retrospectively reviewed and collected data involving age, sex, follow-up period, histological diagnosis, surgical procedures, size and location of defects, size and location of the flaps, venous source of the flaps, direction of the pedicles, closing of donor sites, perioperative chemotherapies, postoperative complications, and the presence of postoperative local recurrence and metastasis. RESULTS: The median follow-up period was 91.5 (range, 15.5-189.0) months. Four patients had defects located around the knee, 3 patients had defects located on the calf, and 2 patients had defects located around the ankle. The mean flap size was 95.6 × 119.4 (range, 50 × 100-130 × 140) mm. Six patients had venous sources from the small saphenous vein and 3 patients had venous sources from the great saphenous vein. The pedicles were proximally based in 4 patients and distally based in 5 patients. All flaps remained viable without any complications. CONCLUSIONS: Our findings showed that the VAF flap was easily elevated and reliable. Furthermore, it was effective in reconstructing soft tissue defects following wide excisions of STTs in the lower leg.

Effects of Different Core Suture Lengths on Tensile Strength of Multiple-Strand Sutures for Flexor Tendon Repair.

Purpose: To compare 2 types of newly devised 8-strand quadruple-looped suture (QLS) techniques with a 6-strand triple-looped suture (TLS) technique; and to assess the effects of different core suture lengths (CSLs) (the length between 2 locking sites of a suture strand) within each suture row on tensile strength. Methods: We repaired 24 flexor tendons from 12 rabbits using the TLS and QLS techniques, with equal CSL (QLS) or unequal CSL (unequal QLS) among each suture row. The QLS was composed of 4 looped sutures on the anterolateral and posterolateral aspects of the tendon. The cross-sectional area of the locking portion of each thread in the QLS was equal to that in the TLS. In the QLS technique, the CSL on each aspect of the tendon was 13 mm. In the unequal QLS technique, the CSL on each aspect of the tendon was 13 and 17 mm. The load at 1- and 2-mm gaps, the maximum load until the 3-mm gap, and the ultimate load were compared among the 3 techniques. Results: The QLS was significantly stronger than the unequal QLS and the TLS for loads at 1-mm and 2-mm gaps, maximum load until 3-mm gap, and ultimate load. There was no significant difference between the unequal QLS and TLS techniques. The QLS technique showed an approximately 30% increase in gap resistance and ultimate strength compared with the TLS technique. Conclusions: The QLS technique showed an estimated increase in tensile strength proportional to the number of suture strands compared with the TLS technique. Our study suggests that a consistent CSL in each suture row provides the highest strength in multistrand sutures consisting of the same configuration of suture rows. Clinical relevance: The QLS technique may reduce the risk for tendon rupture associated with early active mobilization after flexor tendon repair.

The effect of modified locking methods and suture materials on Zone II flexor tendon repair-An ex vivo study.

The failure rate of intrasynovial tendon repair is high due to substantial elongation at the repair site and to the development of adhesions between the tendon's surface and the surrounding digital sheath. To minimize these complications, we sought to reduce the incidence of gapping and to facilitate the initiation of early motion by improving the time zero structural properties of repair. The Winters-Gelberman 8-strand repair technique was modified by adding surface lock loops and by using Fiberwire suture material. Forty-eight canine flexor digitorum profundus tendons were transected and repaired with one of three 8-strand techniques (Pennington modified Kessler, half hitch loops, or surface locking Kessler) using either 3-0 Supramid or 4-0 Fiberwire suture. Biomechanical testing was performed to determine the physiologic and failure mode properties of the repairs. The surface locking Kessler technique improved repair maximum load, load necessary to create a 2 mm repair site gap, and yield force compared to the modified Kessler and half hitch loop techniques. Fiberwire suture improved maximum load, the load necessary to create a 2 mm repair site gap, stiffness, and yield force compared to Supramid suture. Failure occurred by both suture pull out and by suture breakage in the modified Kessler, Supramid suture repair group. Failure occurred consistently by suture breakage in the surface locking Kessler, Supramid suture repair group. These results reveal that a novel locking Kessler repair is significantly stronger than the current state-of-the art flexor tendon suture repair technique. The use of a surface locking Kessler technique with Fiberwire suture markedly improves the mechanical properties of intrasynovial tendon repair by reducing the risk of post-operative gapping and rupture.

Very Distal Radius Wedge Osteotomy for Kienböck's Disease: Case Series.

BACKGROUND: Radius osteotomy is one of the standard surgical procedures for the treatment of Kienböck's disease. Unfortunately, radius osteotomy can result in an incongruous distal radio-ulnar joint (DRUj) postoperatively, because the procedure is performed proximal to the DRUj. METHODS: A very distal radius wedge osteotomy was performed as a 15-degree lateral closing wedge osteotomy with the apex of the wedge distal to that of conventional lateral closing wedge osteotomy; this procedure was developed to avoid postoperative incongruous DRUj. We performed this procedure on 6 patients (stage III-A: 1, stage III-B: 5) with a mean age of 49 years. Clinical and radiographic evaluations were performed at a mean follow-up of 32 months. RESULTS: Wrist pain disappeared in all patients. Mean grip strength improved from 35% to 87% of the contralateral side (p = 0.0255). Mean range of motion, measured as flexion-extension arc, improved from 93 to 128 degrees. Nakamura's score was good in all patient. Mean lunate covering ratio increased from 61% to 90% (p = 0.0151) and mean sigmoid notch inclination angle, a radiographic parameter of DRUj congruency, was not significantly different between pre-operative and final follow-up evaluation. No clinical or radiographic DRUj osteoarthritis findings were observed. CONCLUSIONS: Our procedure of very distal radius wedge osteotomy provided satisfactory clinical results without an incongruous DRUj. This technique might prevent the occurrence of postoperative DRUj osteoarthritis.

Influence of different length of core suture purchase among suture row on the strength of 6-strand tendon repairs.

In multi-strand suture methods consisting of several suture rows, the different length of core suture purchase between each suture row may affect the strength of repairs. We evaluated the influence of the different length of core suture purchase between each suture row on the strength of 6-strand tendon repairs. Rabbit flexor tendons were repaired by using a triple-looped suture technique in which the suture purchase length in each suture row was modified. Group 1, all lengths are 8-mm. Group 2, all lengths are 10-mm. Group 3, two are 10-mm and one is 8-mm. Group 4, one is 10-mm and two are 8-mm. The repaired tendons were subjected to load-to-failure test. The gap strength was significantly greater in Group 1 and Group 2 than in Group 3 and Group 4. This study demonstrates that maintaining equal core suture purchase lengths of each suture row increases the gap resistance.