Itaru Morohashi

Malreduction of syndesmosis injury associated with malleolar ankle fracture can be avoided using Weber's three indexes in the mortise view

PURPOSE Malalignment of syndesmosis is generally associated with a poor outcome, yet occurs at a high rate in malleolar ankle fractures. In this study, we examine whether malreduction of syndesmosis injury associated with malleolar ankle fracture can be avoided using Webers three indexes in the mortise view. MATERIALS AND METHODS Of 156 patients with malleolar ankle fracture who underwent surgery from December 2012 to March 2016 at two medical facilities, 24 patients who received syndesmotic screw fixation were included in the study. Fractures were Danis-Weber types B and C in 8 (8/134, 6.0%) and 16 (16/22, 72.7%) patients, respectively. Using axial computed tomography (CT), we calculated the difference between injured and non-injured sides for each of three parameters: tibiofibular clear space (TFCS), anterior tibiofibular interval (ATF), and fibular rotation (θfib). Malreduction was diagnosed if one or more of the three parameters had an abnormal value. Webers three indexes in the mortise view on the injured side were used to determine whether reduction of syndesmosis was performed successfully. Consistency between the evaluation of reduction of syndesmosis in axial CT images and reevaluation of mortise views was examined by calculation of sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). RESULTS The rate of malreduction of syndesmosis in axial CT images was 29.2% (7/24). Re-evaluation in the mortise view confirmed malreduction of syndesmosis in six of the seven subjects, all of whom also had malreduction based on axial CT images. The one subject in whom malreduction could not be detected in a mortise view showed an abnormal value only for ATF. Use of the mortise view for perioperative diagnosis had a sensitivity of 0.857, specificity of 1.000, PPV of 1.000, and NPV of 0.944. CONCLUSION The results of our study show that malreduction of syndesmosis can be avoided by careful interpretation of intraoperative perspective mortise views based on Webers three indexes. To increase the diagnostic accuracy further, it is important to detect anteroposterior deviation of the fibula in intraoperative lateral views.

Iliopsoas impingement after revision total hip arthroplasty treated with iliopsoas muscle transection

Introduction Iliopsoas tendinitis after revision total hip arthroplasty (THA) is rare and its etiology and optimal treatment are still unclear. We report a case of iliopsoas impingement after revision THA with a Kerboull acetabular reinforcement device requiring two-level iliopsoas muscle transection. Presentation of case A 70-year-old woman presented to our hospital complaining of debilitating right groin pain after revision THA with a Kerboull reinforcement device. She had undergone multiple hip operations after experiencing a pelvic fracture in a motor vehicle accident. A lidocaine nerve block at the level of the Kerboull device resulted in temporary but marked reduction in pain and a diagnosis of psoas impingent. We performed surgery via an anterior approach to release the iliopsoas muscle from the lesser trochanter. After iliopsoas tenotomy was performed, the muscle was still under high tension because of dense adhesions. Repeat transection of the iliopsoas muscle at the level of the anterior branch of the Kerboull device resulted in loosening of the iliopsoas muscle and resolution of impingement. Postoperatively, the patients groin pain completely disappeared, and she can now walk with a single cane and is satisfied with her result. Discussion Adhesions around the iliopsoas muscle likely contributed to the patients groin pain. Open surgery to perform complete release of iliopsoas muscle impingement should be considered in patients with pain after revision THA. Conclusion We reported a patient with Iliopsoas tendinitis after revision THA requiring two-level iliopsoas muscle transection.

A biomechanical study of sacroiliac rod fixation for unstable pelvic ring injuries: verification of the “within ring” concept

PurposeThe aim of this study was to compare the fixation power of sacroiliac rod fixation (SIRF), which was developed based on our original “within ring” concept to exclude the lumbar vertebra from the fixation range, and spinopelvic fixation (SPF) in a biomechanical experiment.MethodsSPF and SIRF were applied to the posterior element in four bones each with the pelvic ring fracture model (AO/OTA classification 61-C1.3). A 300-N axial force was loaded on the fifth lumbar vertebra of the simulated pelvis. Then the stiffness (N/m) and deformation (mm) of SPF and SIRF were determined, and the final displacement (mm) of the fracture region and angular deformity (degrees) were measured. Displacements were measured using the markers at two sites of the sacral fracture [upper margin of the sacral ala (Ala) and second sacral vertebra level (S2)] and one site of the pubic symphysis (PS), and angular deformity was measured at Ala and PS.ResultsIn SPF and SIRF, the mean stiffnesses and deformations showed no statistically significant difference. Only the vertical displacement at Ala differed significantly between SPF and SIRF (p = 0. 045), and the fixing force of SPF was higher. There was no other significant difference in vertical and horizontal displacement. The mean angular deformities also showed no significant difference between the two methods.ConclusionsIn biomechanics experiments, vertical resistance was stronger in SPF-treated than SIRF-treated bone, but stiffness and deformation, horizontal resistance, and angular deformity did not differ significantly.

Acoustic pattern evaluation during cementless hip arthroplasty surgery may be a new method for predicting complications

Background: Although surgeons must perform implantation of the cementless stem during total hip arthroplasty (THA) without complications, assessment is left to the surgeon’s intuitive judgement, which could contain inter/intra-observer bias variety. We therefore asked (1) whether the sound created during the stem implantation could be evaluated objectively and (2) whether those sounds are correlate to the complication specific to the cementless stems. Our hypothesis is that the sounds produced during stem insertion could be quantified and related to the complications. Patients and method: In 71 THAs, we quantified the sound produced during stem insertion and investigated the relationship between these sounds and the occurrence of intraoperative fracture and subsidence. Results: The sound data were divided into two patterns: Patterns A and B. The difference between the peak value (dB) at the most common frequency (near 7 kHz) and the second most common frequency (near 4 kHz) of strikes during the final phase of implantation in Patterns A and B showed a significant difference. Adverse events on intraoperative fracture and subsidence were significantly less common in patients with Pattern A than in those with Pattern B (six of 42 hips with Pattern A and 13 of 29 hips with Pattern B, p = 0.004). Pattern A in predicting a clinical course without those adverse events was 69.2% and the specificity was 68.4%. Positive and negative predictive values were 85.7% and 44.8%, respectively. Conclusion: The sound generated during stem insertion was quantified. Those sound patterns were associated with complications.

Intraoperative dislocation of the trial bipolar cup into the pelvis during bipolar hip arthroplasty – A case report

Introduction Bipolar hip arthroplasty is a good option for treating femoral neck fractures, although some contraindications have been indicated. We report a case of intraoperative dislocation of the trial bipolar cup into the pelvis during bipolar hip arthroplasty. Case presentation A 74-year-old woman underwent bipolar hip arthroplasty for a femoral neck fracture (AO31-B2). She was placed in a lateral decubitus position, and a direct lateral approach was used. During intraoperative trial reduction, the trial bipolar cup became disengaged and dislocated into the anterior space of hip joint. Several attempts to retrieve it failed. The permanent femoral component was inserted, and the wound was closed. The patient was repositioned supine to allow an ilioinguinal approach, and the component was easily removed. She had an uneventful, good recovery. Discussion Several cases of intraoperative dislocation of the femoral trial head during total hip arthroplasty have been reported, this is the first report of dislocation of a bipolar trial cup. A previous report described difficulty retrieving a trial cup. Conclusion We easily removed our trial cup using another approach. It is vital to plan systematically for this frustrating complication.

Treatment of postoperative sciatic nerve palsy after total hip arthroplasty for postoperative acetabular fracture: A case report

Acetabular fracture is usually treated with osteosynthesis. However, in the case of an intra-articular fracture, osteosynthesis can result in arthropathy of the hip joint and poor long-term results, hence, total hip arthroplasty is required. However, in total hip arthroplasty for postoperative acetabular fracture, sciatic nerve palsy tends to develop more commonly than after primary total hip arthroplasty. This is a case report of a 57-year-old Japanese male who had internal skeletal fixation for a left acetabular fracture that had occurred 2 years earlier. One year later, he developed coxarthrosis and severe pain of the hip joint and total hip arthroplasty was performed. After the second surgery, he experienced pain along the distribution of the sciatic nerve and weakness of the muscles innervated by the peroneal nerve, indicating sciatic nerve palsy. We performed a third operation, and divided adhesions around the sciatic nerve. Postoperatively, the anterior hip joint pain and the buttocks pain when the hip was flexed were improved. Abduction of the fifth toe was also improved. However, the footdrop and sensory disturbance were not improved. A year after the third operation, sensory disturbance was slightly improved but the footdrop was not improved. We believe the sciatic nerve palsy developed when we dislocated the hip joint as the sciatic nerve was excessively extended as the hip joint flexed and internally rotated. Sciatic nerve adhesion can occur easily in total hip replacement for postoperative acetabular fracture; hence, adhesiotomy should be conducted before performing hip dislocation to prevent injury caused by nerve tension. The patient agreed that the details of this case could be submitted for publication. The work has been reported in line with the CARE criteria and cite.