Definitive internal fracture fixation followed by staged free flap coverage ("fix followed by flap" protocol) for open Gustilo type IIIB fractures.

BACKGROUND: Although the concept of the "fix and flap" approach, in which definitive fracture fixation and flap coverage are completed in a single procedure at the earliest opportunity may seem ideal for the treatment of Gustilo type IIIB open fractures, the individual circumstances of patients, such as polytrauma or multiple fracture cases may not allow for the immediate fracture fixation and flap coverage ("fix and flap" approach). In our hospital, patients with Gustilo type IIIB open fractures are treated with definitive internal fixation of the fracture followed by staged flap coverage ("fix followed by flap" protocol) when the "fix and flap" approach was not feasible due to the patient's condition or difficulty in coordinating surgery schedules. The "fix followed by flap" protocol provides benefits in terms of flexibility in adjusting the surgical timetable, simplifying the planning of flap coverage following fracture fixation, and minimizing individual surgical invasion. METHODS: We reviewed 10 cases of severe open fractures treated with the "fix followed by flap" protocol and evaluated their outcomes. All surgical procedures, including wound debridement, fracture fixation, and flap coverage, were performed by orthoplastic surgeons specializing in both fracture surgery and microsurgery including soft tissue reconstruction. RESULTS: All free flaps survived, and no partial necrosis was observed. None of the patients developed postoperative deep infection up to the last follow-up. Fracture union was achieved in all patients with or without autologous bone grafts. The median time for union was 9.4 months (range, 4-12 months). CONCLUSIONS: This study presents favorable outcomes of treatment for Gustilo type IIIB open fractures with fracture fixation followed by staged flap coverage ("fix followed by flap" protocol). Despite a delay in flap coverage, the consistency of treatment provided by orthoplastic surgeons may have contributed to the favorable outcomes in this study.

Bone and soft tissue reconstruction with tendon balance in severe foot trauma.

In severe foot trauma, it is difficult to determine the level of amputation when the crush injury is severe. We report a case of amputation near Lisfranc that achieved forefoot amputation-like results by using bone and soft tissue reconstruction while considering tendon balance. The patient was a 40-year-old male. The patient's left leg was caught in a garbage truck and sustained a crush injury. The second to fifth metatarsals were amputated at the diaphysis, and a high degree of instability of the Lisfranc joint was observed. A high degree of contamination was detected in the patient's wound, and the second to fifth toes were amputated at the Lisfranc joint during the initial treatment. The ends of the tibialis anterior, tibialis posterior and peroneus longus were preserved. On day 5 in the hospital, Lisfranc joint fixation of the hallux, amputation of the first metatarsal and reconstruction of the peroneus brevis were performed. On day 13, extensor hallucis longus tendon transfer and free anterolateral thigh flap were performed. On day 80, the patient was able to walk in regular shoes or non-orthopedic shoes. One year after reconstructive surgery, the patient had an average SAFE-Q score of 86.2 and mild varus deformity of the foot remained. In cases of severe foot trauma, the aim of reconstruction should be partial forefoot amputation whenever possible.

Cross-Limb Vascular Shunting for Traumatic Popliteal Artery Injury.

BACKGROUND: Popliteal artery injury (PAI) is a challenging trauma that requires prompt and accurate treatment since the probability of lower-limb amputation increases with the ischemic time. Intravascular shunting and cross-limb vascular shunting (CLS) are used as temporary vascular shunting (TVS) methods to shorten the ischemic time for limb vascular injury. CLS involves sending blood from an artery in a healthy body part to a peripheral vessel in an injured part to immediately resume blood flow to the injured limb. For closed injuries including PAI, CLS may be performed without exploring and identifying the arterial stumps and it enables early reperfusion to the ischemic limb. We report the case series of traumatic PAI treated using CLS and verify the usefulness of CLS. METHODS: All patients with traumatic PAI treated with CLS at our institution between August 2013 and December 2021 were included. Demographic and clinical patient characteristics were extracted from the medical records. Comorbid injuries, severity of acute limb ischemia based on the Rutherford grading scale, time from injury to reperfusion by CLS, time from injury to completion of artery, and the use of fasciotomy were investigated. As outcomes, we investigated the presence or absence of lower extremity amputation during the course of treatment. RESULTS: We used CLS as treatment for 5 cases with traumatic PAI. Based on the Rutherford grading scale for acute limb ischemia, there were one limb with grade 2B and 4 with grade 3. Amputation of the lower extremities was avoided except for 1 extremity in which arterial reconstruction was not achieved due to unexplained cardiac arrest during surgery. CONCLUSIONS: CLS enables early reperfusion of the injured limb and is effective as a TVS method for traumatic PAI with severe ischemia or soft tissue damage.

Management of bone loss in acute severe open tibial fractures: a retrospective study of twenty nine cases-a treatment strategy with bone length preservation.

PURPOSE: The present study investigated the outcomes of bone loss associated with acute open tibial fractures classified as Gustilo-Anderson classification grade III B (GIIIB) using a bone length preservation strategy. METHODS: Among acute GIIIB open tibial fractures, 29 limbs of 29 patients requiring bone loss treatment were included. The reconstruction methods for bone loss were selected among the Masquelet technique (MT), bone transport (BT), acute shortening followed by gradual lengthening (ASGL), and free vascularized fibula graft (FVFG). Primary outcome measures were the rate of bone union and time to bone union. RESULTS: The median radiographic apparent bone gap (RABG) was 46.75 mm. Bone loss was treated with ASGL only in two patients in whom it was not possible to cover large soft tissue defects by a single free latissimus dorsi (LD) myocutaneous flap (with the serratus anterior (SA) muscle). The other 27 patients underwent soft tissue reconstruction and bone loss treatment with the preservation of bone length, including the MT for 23, BT for six, and FVFG for one. The bone union rate was 75.9%, and the median time to bone union was six months. Salvage surgeries were performed on all seven patients with nonunion; all of whom eventually achieved bony union. CONCLUSION: Bone loss associated with acute GIIIB open tibial fractures were treated with "bone length preservation" if the size of the soft tissue defect was less than the size that was covered by a single LD myocutaneous flap (with the SA muscle).

Risk factors for over-telescoping in reverse oblique intertrochanteric fractures.

PURPOSE: Postoperative over-telescoping (OT) with lag screws is often observed in reverse oblique intertrochanteric fractures. This study aimed to clarify the risk factors of OT in patients with reverse oblique intertrochanteric fractures. METHODS: Electronic medical records of patients diagnosed with reverse oblique intertrochanteric fractures using plain radiography who underwent operative fixation with an intramedullary nail between August 2013 and December 2019 were reviewed. Patients were classified into two groups according to the Futamura classification: lateral wall pattern (LW) and reverse oblique pattern (RO). The incidence of OT in the LW and RO groups was compared. Also, we compared the incidence of OT for each reduction type in the LW group. RESULTS: Twenty patients had LW, and nine had RO. OT was observed in eight fractures (42.1%) in the LW group but not in the RO group. The incidence of OT was significantly higher in the LW group than in the RO group (P = 0.0261). Among the 19 fractures with LW, OT was observed in 7 of 10 and 1 of 9 fractures with postoperative reduction in the intramedullary and extramedullary or anatomical types, respectively. In the LW group, the incidence of OT was significantly higher in fractures with postoperative reduction in the intramedullary type than in those of the extramedullary or anatomical type (P = 0.0198). CONCLUSION: Our study showed that the incidence of OT was significantly higher in LW than in RO and that postoperative reduction in the intramedullary type in LW was a risk factor for OT.

Pull-in suture: a novel reconstruction technique for tendon avulsion injury at the musculotendinous junction associated with forearm open fracture.

We present three cases of strong one-staged tendon reconstruction for musculotendinous junction avulsion tendon injuries, and called it a 'pull-in suture'. The clinical outcomes of this method are comparable to those of tendon transfer; it is an effective reconstruction method that should be considered as an initial treatment procedure.

Discovery of a novel 2-(1H-pyrazolo[3,4-b]pyridin-1-yl)thiazole derivative as an EP1 receptor antagonist and in vivo studies in a bone fracture model.

We describe a medicinal chemistry approach to the discovery of a novel EP1 antagonist exhibiting high potency and good pharmacokinetics. Our starting point is 1, an EP1 receptor antagonist that exhibits pharmacological efficacy in cystometry models following intravenous administration. Despite its good potency in vitro, the high lipophilicity of 1 is a concern in long-term in vivo studies. Further medicinal chemistry efforts identified 4 as an improved lead compound with good in vitro ADME profile applicable to long term in vivo studies. A rat fracture study was conducted with 4 for 4 weeks to validate its utility in bone fracture healing. The results suggest that this EP1 receptor antagonist stimulates callus formation and thus 4 has potential for enhancing fracture healing.

Enhancement of hemocompatibility of the MERA monopivot centrifugal pump: toward medium-term use.

The MERA monopivot centrifugal pump has been developed for use in open-heart surgery, circulatory support, and bridge-to-decision for up to 4 weeks. The pump has a closed-type, 50-mm diameter impeller with four straight paths. The impeller is supported by a monopivot bearing and is driven by a radial-flux magnet-coupling motor. Because flow visualization experiments have clarified sufficient pivot wash and stagnation at the sharp corner of the pivot support was suggested, sharp corners were removed in the design stage. The index of hemolysis of the pump operating at more than 200 mm Hg was found to be lower than that of a commercial pump. Four-week animal tests were then conducted two times; improvement of thrombus formation was seen in the female pivot through modification of female pivot geometry. Overall antithrombogenicity was also recorded. Finally, to assure mid-term use, an additional 4-week durability test revealed that the rate of the axial pivot wear was as small as 1.1 µm/day. The present in vitro and in vivo studies revealed that the MERA monopivot centrifugal pump has sufficient hemocompatibility and durability for up to 4 weeks.

Preventive effects of raloxifene, a selective estrogen receptor modulator, on monocrotaline-induced pulmonary hypertension in intact and ovariectomized female rats.

We investigated whether the chronic treatment with raloxifene, a selective estrogen receptor modulator, prevents the development of monocrotaline-induced pulmonary hypertension in ovary-intact and ovariectomized female rats. Four weeks after a single subcutaneous injection of monocrotaline (60 mg/kg), right ventricular systolic pressure, right ventricle-to-left ventricle plus septal weight ratio, pulmonary arterial medial thickening and endothelin-1 levels in right ventricular tissue increased significantly in both female rats, compared with saline-treated control rats. These monocrotaline-induced alterations were much greater in ovariectomized rats than the changes in intact females. Daily oral administration of raloxifene (10 mg/kg/day for 4 weeks) significantly attenuated the increase in right ventricular systolic pressure to the same levels in both groups of animals, but raloxifene suppressed the increases in right ventricle-to-left ventricle plus septal weight ratio and pulmonary arterial medial thickness more efficiently in ovariectomized females than the case with intact females. In addition, raloxifene completely suppressed the increase in right ventricular endothelin-1 levels in ovariectomized rats, but not in intact females. These data suggest that chronic treatment with raloxifene effectively prevents the development of monocrotaline-induced pulmonary hypertension in ovariectomized female rats than in intact females, at least in part, by suppressing right ventricular endothelin-1 overproduction.

Antithrombogenic properties of a monopivot magnetic suspension centrifugal pump for circulatory assist.

The National Institute of Advanced Industrial Science and Technology (AIST) monopivot magnetic suspension centrifugal pump (MC105) was developed for open-heart surgery and several weeks of circulatory assist. The monopivot centrifugal pump has a closed impeller of 50 mm in diameter, supported by a single pivot bearing, and is driven through a magnetic coupling to widen the fluid gap. Design parameters such as pivot length and tongue radius were determined through flow visualization experiments, and the effectiveness was verified in preliminary animal experiments. The maximum overall pump efficiency reached 18%, and the normalized index of hemolysis tested with bovine blood was as low as 0.0013 g/100 L. Animal experiments with MC105 were conducted in sheep for 3, 15, 29, and 35 days in a configuration of left ventricle bypass. No thrombus was formed around the pivot bearing except when the pump speed was reduced by 20% of normal operational speed, which reduced the pump flow by 40% to avoid inlet suction. Subsequently, the antithrombogenic design was verified in animal experiments for 5 weeks at a minimum rotational speed of greater than 1500 rpm and a minimum pump flow greater than 1.0 L/min; no thrombus formation was observed under these conditions.

[Symmetrical bilateral epidural hematoma after head injury in the mid parietooccipital region: case report].

The authors presented a patient with acute symmetrical bilateral epidural hematomas, which are rare but life threatening. A 72-year-old male accidentally fell from the roof at a height of about 3 meters and hit his head against the ground. He was transferred to the emergency ward in our hospital. On admission, he was alert and had no neurological deficits. Skull X-ray film revealed a depressed fracture in the mid parietoocipital region and bilateral linear fractures extending from the parietal regions to the temporal regions. CT scan showed symmetrical bilateral epidural hematomas in the both parietotemporal regions. His consciousness deteriorated to be drowsiness about one hour after admission. An additional CT scan revealed enlargement of the both epidural hematomas and impending tentorial herniation. Therefore, an emergency operation was called for. For rapid decompression of the brain, bilateral craniotomies were carried out simultaneously by the two neurosurgeon-groups involved and bilateral epidural hematomas were also simultaneously removed. Injury of both of the middle meningeal arteries was revealed to be the cause of the bilateral epidural hematomas. Clinical course after operation was uneventful and the patient was discharged without any neurological deficit. Simultaneous bilateral craniotomies and removal of the epidural hematomas would have contributed to obtaining the good result in this patient.