Lower body bone fractures have high mortality rates and poor prognosis in the patients with hemodialysis.

INTRODUCTION: The objective of the current study was to investigate the association between lower body bone fractures occurring during maintenance hemodialysis and prognosis. METHODS: This study included 151 hemodialysis patients at the dialysis center of our hospital as of December 2017, and data were systematically gathered from medical records over a period of 5 years, concluding in December 2022. RESULTS: Fourteen patients, 3.0 per 100 person-years, in 151 hemodialysis patients suffered from lower body bone fractures. The ratio of males was significantly lower, and age was significantly higher in the lower body bone fracture group than in the no lower body bone fracture group. Duration of hemodialysis prior to entry into this study was significantly shorter in the lower body bone fracture group than in the no lower body bone fracture group. Serum albumin was significantly lower and alkaline phosphatase was significantly higher in the lower body bone fracture group than in the no lower body bone fracture group. Mortality rate was significantly higher in the lower body bone fracture group (85.7%) compared to no lower body bone fracture group (28.5%) (p = 0.01). Kaplan-Meier survival curves for mortality showed that lower body bone fracture group had poor prognosis compared to no lower body bone fracture group. Multivariable-adjusted odds ratio for mortality were significantly higher for cases with lower body bone fractures. CONCLUSION: Lower body bone fractures have high mortality rates and poor prognosis in the patients with hemodialysis.

Bone morphology and physical characteristics of the pro-cyclist hip joint.

PURPOSE: This study aimed to investigate the radiographic findings for the hip joint and hip range of motion in professional cyclists, and to determine their bone morphology and physical characteristics. The effects of physical characteristics on athletic performance were examined in terms of metabolic efficiency using simulation analysis. METHODS: We performed a case-control research study on 22 hips in 11 male professional cyclists (average age 28.5, height 1.73 m, weight 77.6 kg). Thirty hips in 15 healthy male volunteers were selected as controls. As radiographic evaluations, acetabular dysplasia was assessed on standardized radiographs. During physical evaluations, the hip range of motion was examined. We used simulation analysis to investigate the metabolic efficiency in the different cycling forms. RESULTS: The radiographic evaluations showed a significant difference in the incidence of acetabular dysplasia (p = 0.01): 59% (13/22 hips) in the pro-cyclist group versus 10% (3/30 hips) in the control group. The physical evaluations revealed significant differences in the hip internal rotation angle (p = 0.01), with greater ranges of internal rotation in the pro-cyclist group versus the control group. The simulation analyses showed that metabolism was reduced in the cycling form with hip internal rotation, especially in the lower extremities. CONCLUSIONS: Pro-cyclists showed a high frequency of acetabular dysplasia and superior hip internal rotation. According to the cycling model analyses, hip internal rotation allowed pedaling with reduced metabolic power.

Serial Magnetic Resonance Arthrography for a Midsubstance Capsular Tear in a Patient With Traumatic Anterior Shoulder Instability.

The natural history of midsubstance capsular tears (MCTs) is unclear. We herein describe a case of MCT observed using serial magnetic resonance (MR) arthrography. A 46-year-old woman presented with excessive external rotation of the left glenohumeral joint, resulting in an initial anterior dislocation of the left shoulder. She subsequently developed recurrent shoulder joint dislocations. MR arthrography revealed an MCT without a Bankart lesion three months after the initial dislocation. She opted for nonoperative treatment, but the shoulder instability did not improve. The second MR arthrography, nine months after the initial dislocation, showed no natural healing of the MCT. The third MR arthrography, 12 months after the initial dislocation, also showed no natural healing. Her shoulder instability remained persistent. The patient then decided to have surgery. Arthroscopy revealed a large capsular defect extending from the glenoid to the humeral head in the anterior inferior glenohumeral ligamentous complex. The MCT was repaired with the placement of nonabsorbable sutures in a side-to-side fashion. At the final follow-up, three years postoperatively, the patient had no anterior shoulder instability. The Rowe score was 100 points. MR arthrography showed good repair integrity of the MCT at one year postoperatively. Serial MR arthrography was useful for both the patient and the shoulder surgeon in considering the treatment of the MCT, facilitating an accurate and qualitative assessment of whether natural healing of the MCT had been achieved.

Minimum 10-Year Survivorship of Uncemented Acetabular Reconstruction With Bulk Femoral Head Autografting in Crowe Type IV Developmental Hip Dysplasia.

BACKGROUND: In total hip arthroplasty (THA) for severe dislocations such as Crowe type IV developmental dysplasia of the hip (DDH), sufficient bone volume for stable fixation of the acetabular component can be achieved by placing a reinforcing bone graft prepared from the resected femoral head into the deficient acetabulum. The purpose of the current study was to examine the long-term survivorship of uncemented THA in conjunction with a bulk femoral head autograft in patients who have Crowe type IV DDH. METHODS: A total of 35 patients (42 hips) who have Crowe type IV DDH and underwent THA using uncemented cup fixation with bulk femoral head autografting were followed up for a mean period of 15.0 years (range, 10.0 to 20.0) postoperatively. Anteroposterior pelvic radiographs were used for measurements such as the horizontal coverage of the grafted bone and the center-edge angle. Kaplan-Meier survivorship analyses were performed with revision of the acetabular component as the endpoint. RESULTS: The Kaplan-Meier analysis indicated 15-year survival rates of 90.4%. The mean horizontal coverage of grafted bone was 46.1% (range, 23.7 to 66.0), and there were 16 cases with horizontal coverage of ≥ 50%. There was no difference in the appearance of a thin (< 1 mm) radiolucency line around the cup between cases with < 50% versus ≥ 50% of the horizontal coverage of grafted bone (4 versus 2 hips; P = .446). Trabecular bridging and remodeling were seen in all cases after mean periods of 4.1 and 9.0 months postoperatively, respectively. Trabecular reorientation was seen in 41 of 42 hips (97.6%) at a mean follow-up of 19.9 months. CONCLUSIONS: Acetabular reconstruction with femoral bulk bone grafting for Crowe type IV DDH resulted in high survival rates and was a good method to restore bone stock and obtain long-term fixation.

Return to Sports Activity After Microfracture for Osteochondral Lesion of the Talus in Skeletally Immature Children.

BACKGROUND: Osteochondral lesions of the talus (OLTs) are among the common sports-related injuries. However, there are few reports on the return to sports after OLT surgery in skeletally immature children. This study was performed to evaluate the return to sports after microfracture for OLTs in skeletally immature children. METHODS: This study involved 17 ankles of 16 patients (mean age, 13.2 years; range, 10-16 years) with open tibial epiphyses on magnetic resonance imaging (MRI) who underwent microfracture for OLTs <10 mm in diameter and confirmation of lesion instability under arthroscopy. Nine of 17 ankles had additional lateral ankle ligament stabilization. All patients were participating in some form of sports. The Japanese Society for Surgery of the Foot (JSSF) score, Ankle Activity Score (AAS), return to sports rate, lesion size, grade of subchondral bone marrow edema, and Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score on MRI were evaluated after microfracture. The mean postoperative follow-up period was 53.5 months. RESULTS: The mean JSSF score significantly improved from 76.1 points preoperatively to 94.9 points at the final follow-up (P < .01). The mean AAS showed no change from preoperative state to final follow-up. The return to sports rate was 100%. The lesion size significantly decreased from 76.3 to 56.7 mm2 in area (P = .02) and from 283.2 to 185.6 mm3 in volume (P = .05). The bone marrow edema grade decreased in 8 of 17 ankles. The total MOCART score showed a significant improvement from 6 months to 1 year postoperatively (P = .05). CONCLUSION: All skeletally immature children who underwent microfracture for OLTs in this study were able to return to sports activity and showed improvements in clinical scores and MRI parameters. Microfracture may be considered an effective first-line treatment for OLTs <10 mm in diameter in skeletally immature athletes. LEVEL OF EVIDENCE: Level IV, retrospective case-control study.

Corticosteroid-associated osteonecrosis of the femoral head in an 87-year-old patient following treatment for COVID-19-associated pneumonia: A case report.

Coronavirus disease 2019 is known to cause severe acute respiratory syndrome, and serious cases need to be treated with corticosteroids. Herein, we report an 87-year-old woman who developed bilateral osteonecrosis of the femoral head after corticosteroid treatment for coronavirus disease 2019-related pneumonia. Sixteen months after treatment, she developed right hip pain without any evidence of trauma. A diagnosis of bilateral osteonecrosis of the femoral head was made based on sclerotic bands on plain radiographs and low-signal bands on T1-weighted magnetic resonance images. The patient underwent right total hip arthroplasty 4 months after symptom onset. Histological examination of the resected femoral head revealed pathological evidence of osteonecrosis. The postoperative course was good, and the patient can now walk unassisted. To the best of our knowledge, this is the first report of histologically proven osteonecrosis after corticosteroid therapy for coronavirus disease 2019-related disease.

Incidence and clinical outcome of lateral femoral cutaneous nerve injury after periacetabular osteotomy.

Aims: Lateral femoral cutaneous nerve (LFCN) injury is a complication after periacetabular osteo-tomy (PAO) using an anterior approach, which might adversely affect the outcome. However, no prospective study has assessed the incidence and severity of this injury and its effect on the clinical outcomes over a period of time for longer than one year after PAO. The aim of this study was to assess the incidence and severity of the symptoms of LFCN injury for ≥ three years after PAO and report its effect on clinical outcomes. Methods: A total of 40 hips in 40 consecutive patients who underwent PAO between May 2016 and July 2018 were included in the study, as further follow-up of the same patients from a previous study. We prospectively evaluated the incidence, severity, and area of symptoms following LFCN injury. We also recorded the clinical scores at one year and ≥ three years postoperatively using the 36-Item Short Form Health Survey (SF-36) and Japanese Orthopaedic Association Hip Disease Evaluation Questionnaire (JHEQ) scores. Results: A total of 20 patients (50%) had symptoms of a LFCN injury at one year after PAO. At ≥ three years postoperatively, the symptoms had completely resolved in seven of these patients and 13 (33%) had persistent symptoms. The severity and area of symptoms did not significantly differ between one and ≥ three years postoperatively. The JHEQ showed significant differences in the patient satisfaction and mental scores between those with and those without sypmtoms of LFCN injury at ≥ three years postoperatively, while there was no significant difference in the mean SF-36 scores. Conclusion: The incidence of LFCN injury after PAO using an anterior approach is high. The outcome of PAO, ≥ three years postoperatively, is poorer in patients with persistent symptoms from a perioperative LFCN injury, in that patient satisfaction and mental health scores are adversely affected.

Recurrent Subchondral Insufficiency Fracture of the Femoral Head: A Case Report.

Introduction: Subchondral insufficiency fracture (SIF) of the femoral head has been reported to occur in older women with osteoporosis. No cases with recurrence of SIF at another site in the ipsilateral femoral head have been described. Case Report: We report a case of a 75-year-old woman with recurrent SIF at another site in the ipsilateral femoral head. SIF was first observed at an anterolateral site on the femoral head and treated non-operatively. The hip pain disappeared after 3 months but recurred 5 months later when another SIF was newly observed at a posterolateral-to-medial site on the femoral head. This SIF was also treated non-operatively. Five months later, the pain was alleviated, but progression of osteoarthritis was seen on X-rays. Conclusion: After an initial SIF, the possibility of recurrence should be considered if pain recurs, even on the ipsilateral side.

Soft Tissue Stabilization of the Hinge Position for Lateral Closing-Wedge Distal Femoral Osteotomy: An Anatomic Study.

Background: Soft tissue plays an important role in stabilizing the hinge point for osteotomy around the knee. However, insufficient data are available on the anatomic features of the soft tissue around the hinge position for lateral closing-wedge distal femoral osteotomy (LCWDFO). Purpose: To (1) anatomically analyze the soft tissue around the hinge position for LCWDFO, (2) histologically analyze the soft tissue based on the anatomic analysis results, and (3) radiologically define the appropriate hinge point to prevent unstable hinge fracture based on the results of the anatomic and histological analyses. Study Design: Descriptive laboratory study. Methods: In 20 cadaveric knees (age, 82.7 ± 7.8 years; range, 60-96 years), the soft tissue of the distal medial side of the femur was anatomically analyzed. The thicknesses of the periosteum and direct insertion of the adductor tendon (AT) were histologically examined and measured using an electron microscope. The thickness of the periosteum was visualized graphically, and the graph of the periosteum and radiograph of the knee were overlaid using image editing software. The appropriate hinge position was determined based on the periosteal thickness and attachment of the AT. Results: The mean thickness of the periosteum of the metaphysis was 352.7 ± 58.6 µm (range, 213.6-503.4 µm). The overlaid graph and radiograph revealed that the thickness of the periosteum changed at the part corresponding to the transition between the diaphyseal and metaphyseal ends of the femur. The mean width of the AT attached to the distal medial femur from the adductor tubercle toward the distal direction was 7.9 ± 1.3 mm (range, 6.3-9.7 mm). Conclusion: Results indicated that the periosteum and AT support the hinge for LCWDFO within the area surrounded by the apex of the adductor tubercle and the upper border of the posterior part of the lateral femoral condyle. Clinical Relevance: When the hinge point is located within the area surrounded by the apex of the adductor tubercle and the upper border of the posterior part of the lateral femoral condyle, these soft tissues work as stabilizers, and there is no risk of cutting into the joint space.

Outcomes of Balloon Kyphoplasty for Vertebral Compression Fractures in Patients with Diffuse Idiopathic Skeletal Hyperostosis at the Distal End or Adjacent Vertebra of the Fused Segments.

STUDY DESIGN: A retrospective cohort study. PURPOSE: To investigate the outcomes of balloon kyphoplasty (BKP) for vertebral compression fractures (VCFs) at the distal end or adjacent vertebra of the fused segments in patients with diffuse idiopathic skeletal hyperostosis (DISH). OVERVIEW OF LITERATURE: Vertebral fractures in the midportion of the fused segments in patients with DISH are generally unstable; thus, immobilization is recommended. However, VCFs classified as type A in the AO classification are observed at the distal end and adjacent vertebra of the fused segments, and treatment strategies for VCFs associated with DISH remain controversial. METHODS: The outcomes of 72 patients who underwent BKP for VCFs between 2015 and 2021 were retrospectively investigated. Patients with DISH were assigned to group D (n=21), whereas those without DISH were assigned to group ND (n=51). Back pain, incidence of subsequent adjacent fractures, reoperation rates, and local kyphosis were statistically analyzed. RESULTS: VCFs in group D occurred at the distal end or adjacent vertebra of the fused segments, and no fractures occurred in the midportion of the fused segment. Back pain improved in both groups, with no significant differences between them. Subsequent adjacent fractures were observed in three of the 21 patients in group D and 11 of the 51 patients in group ND, with no significant difference between them. Reoperation was performed in one patient each in groups D and ND, with no significant difference between the groups. Postoperatively, local kyphosis progressed significantly in group D. CONCLUSIONS: Although local kyphosis is more advanced in patients with DISH, BKP is effective for VCFs at the distal end or adjacent vertebra of the fused segments and may be useful in older patients with high complication rates.

Erratum for Factors Affecting Home Discharge of Older Adults with Cervical Spinal Cord Injury in Japan Regional Population.

[This corrects the article DOI: 10.22603/ssrr.2023-0045.].

Vertical Subluxation Caused by Infection Around the Odontoid Process: A Case Report.

Introduction: There are few reports of cases with vertical subluxation. We report our experience of a vertical subluxation of the atlantoaxial joint caused by infection. Case Report: A 63-year-old man had a 5-month history of neck pain. He was treated for rheumatoid arthritis by a local doctor. At admission to our hospital, he had neck pain and complained of dysphagia and hoarseness. His white blood cell count and C-reactive protein were 7200/mm3 and 4.86 mg/dL. Cervical X-ray showed atlantoaxial subluxation. Computed tomography showed osteolysis around the odontoid process, including the atlantooccipital and atlantoaxial joints, causing vertical subluxation. Magnetic resonance imaging showed spinal cord and brainstem compression and the presence of fluid. Gadolinium-enhanced magnetic resonance imaging showed enhancement around the odontoid process. We performed occipital-cervical spine fixation and C1 laminectomy. Following surgery, his symptoms completely resolved. Bone fusion was confirmed 6 months after surgery. Conclusion: If subluxation of the upper cervical spine occurs rapidly, infection should be considered.

The role of torsional stress in the development of subchondral insufficiency fracture of the femoral head: A finite element model analysis.

BACKGROUND: Subchondral insufficiency fracture of the femoral head generally occurs without evidence of trauma or with a history of minor trauma. Insufficient bone quality is considered one cause; however, the detailed mechanism of fracture development at the subchondral area (SA) is not understood. The aim of this study was to clarify the directions of force that cause subchondral fracture using finite element model analysis. METHODS: Two types of finite element models were generated from the CT data of femurs obtained from three individuals without osteoporosis (normal models) and another three with osteoporosis (osteoporosis models). Three directions of force, including compressive, shearing, and torsional, were applied to the femoral head. The distribution of von Mises stress (Mises stress) was evaluated at the SA, principal compressive trabeculae (PC), and principal tensile trabeculae. RESULTS: Under compressive force, the mean Mises stress value was greatest at the PC in both the normal and osteoporosis models. Under shearing force, the mean Mises stress value tended to be greatest at the SA in the normal model and at the PC in the osteoporosis model. Under torsional force, the mean Mises stress value was greatest at the SA in both types of models. CONCLUSIONS: The torsional force showed the greatest Mises stress at the SA in both the normal and osteoporosis models, suggesting the importance of torsion as a possible force responsible for subchondral insufficiency fracture development.

Side-to-side variability in the femoral neck anteversion angle: A study of the Japanese population with osteonecrosis of the femoral head.

BACKGROUND: Side-to-side variability in the femoral neck anteversion angle (FA) reportedly varies from 0.0° to 17.3°. To investigate the side-to-side variability in the FA and the relationship between the FA and the morphology of the acetabulum in the Japanese population, we performed a three-dimensional computed tomography (CT)-based study involving patients with osteonecrosis of the femoral head (ONFH). METHODS: CT data were obtained from 170 nondysplastic hips of 85 patients with ONFH. The FA and acetabular coverage parameters, including the acetabular anteversion angle, acetabular inclination angle, and acetabular sector angle in the anterior, superior, and posterior directions, were measured using three-dimensional CT. The distribution of the side-to-side variability in the FA was evaluated separately for each of the five degrees. RESULTS: The mean side-to-side variability in the FA was 6.7° ± 5.3° (range, 0.2°-26.2°). The distribution of the side-to-side variability in the FA was 0.0°-5.0° in 41 patients (48.2%), 5.1°-10.0° in 25 patients (29.4%), 10.1°-15.0° in 13 patients (15.3%), 15.1°-20.0° in 4 patients (4.7%), and >20.1° in 2 patients (2.4%). There was a weak negative correlation between the FA and anterior acetabular sector angle (r = -0.282, P < 0.001) and a very weak positive correlation between the FA and acetabular anteversion angle (r = 0.181, P < 0.018). CONCLUSIONS: The mean side-to-side variability in the FA was 6.7° ± 5.3° (range, 0.2°-26.2°) in Japanese nondysplastic hips, and about 20% of the patients had a side-to-side variability of >10°.

Factors Affecting Home Discharge of Older Adults with Cervical Spinal Cord Injury in Japan Regional Population.

Introduction: Older adults with cervical spinal cord injury (CSCI) often have a poor prognosis due to the high number of complications, decreased motivation to rehabilitation, and poor response to treatment. This study aimed to investigate the characteristics of CSCI in Japanese older adults and examined the factors influencing their discharge home. Methods: In this retrospective cohort study, we extracted data on consecutive cases with CSCI between 2005 and 2020 from the study hospital's database. Patients over 65 years old who were admitted to the hospital within 14 days of injury were selected. A univariate analysis was performed between the home discharge and out-of-home discharge groups. In addition, binary logistic regression analysis of admission findings and patient background was performed to examine independent factors influencing home discharge. Results: Of the 219 patients included, 90 (41.1%) were eventually discharged to home. Comparing home discharge and out-of-home discharge groups revealed significant differences in age at injury, length of hospital stay, neurological level of injury (NLI), percentage of American Spinal Injury Association (ASIA) Impairment Scale (AIS: A), percentage of living alone, ASIA motor score (AMS), and Spinal Cord Independence Measure (SCIM) at initial visit and discharge. Binary logistic regression analysis revealed that old age (over 75 years old) at injury (odds ratio [OR]: 0.31, 95% CI: 0.16-0.60, P<.001), living alone (OR: 0.22, 95% CI: 0.03-0.42, P<.01), high level of injury (i.e., NLI: C1-4; OR: 0.22, 95% CI: 0.09-0.53, P<.0001), and percentage of AIS: A at admission (OR: 0.09, 95% CI: 0.04-0.24, P<.001) were independent factors that influenced home discharge. Conclusions: More than 50% older adults with CSCI were discharged to a place other than their own home. Age, percentage of AIS: A, living alone, and high level of injury at admission were independent factors that influenced home discharge.

Assessment of the Hip Flexor Muscles Shortly after Curved Periacetabular Osteotomy using Magnetic Resonance Imaging.

BACKGROUND: Curved periacetabular osteotomy requires detachment and retraction of the hip flexors. In this study, we evaluated hip flexor muscle status by magnetic resonance imaging (MRI) shortly after curved periacetabular osteotomy. METHODS: We retrospectively evaluated 60 hips of 56 patients by MRI 1 week and 3 months after curved periacetabular osteotomy performed from August 2017 to December 2019. We classified the condition of the flexors as follows: Grade 0, normal; Grade I, strain/edema; Grade II, partial tear; and grade III, complete tear. RESULTS: At 1 week after surgery, the iliacus muscle was classified as grades I and II in 12.0 and 88.0% of hips; psoas as grades 0, I and II in 22.0, 72.0, and 6.0%; sartorius muscle as grades 0, I and II in 6.0, 62.0, and 32.0%; and rectus femoris muscle as grades 0 and I in 86.0 and 14.0%, respectively. At 3 months, 82.0, 88.0, and 96.0% of psoas, sartorius, and rectus femoris muscles, respectively, had improved to grade 0, whereas the iliacus was grades I and II in 94.0 and 6.0%, respectively. These changes in the iliacus muscle at 3 months were not significantly associated with patient characteristics, radiographic data, or clinical scores. CONCLUSIONS: All the iliacus, 78% of psoas, 94% of sartorius, and 14% of rectus femoris muscles appeared abnormal on MRI 1 week after curved periacetabular osteotomy. However, at 3 months, only 18% of psoas, 12% of sartorius, and 4% of rectus femoris muscles appeared abnormal, whereas all iliacus muscles still appeared abnormal. These abnormalities did not significantly affect clinical scores.

Radiologic foot alignment and clinical outcome after percutaneous drilling for symptomatic accessory navicular in skeletally immature children.

Various surgical treatments are available for a symptomatic AN, including percutaneous drilling (PD). PD is reportedly effective for ANs in skeletally immature children. However, no reports have described the foot alignment after PD in skeletally immature children. This study was performed to compare the radiographic parameters between the preoperative period and the final follow-up after PD for symptomatic ANs in skeletally immature children. From October 2013 to December 2020, PD was performed on 13 feet in 10 skeletally immature children. The patients comprised 5 boys and 5 girls with a mean age at surgery of 11.9 years. The mean follow-up period was 14.8 months. We measured 5 radiographic findings preoperatively and at the final follow-up: calcaneal pitch angle (CPA), talocalcaneal angle (TCA), talonavicular coverage angle (TNCA), anteroposterior talo-first metatarsal angle (ATMA), and lateral talo-first metatarsal angle (LTMA). Ten feet were assessed as excellent, 1 as fair, and 2 as poor. Ten unions (76.9%) were achieved among the 13 feet. The mean CPA improved from 16.4 ±â€…4.1 degrees preoperatively to 18.2 ±â€…3.4 degrees at the final follow-up, the TCA improved from 43.0 ±â€…3.7 to 45.2 ±â€…4.4 degrees, and the TNCA improved from 19.9 ±â€…4.4 to 15.4 ±â€…5.0 degrees (P < .05). The ATMA and LTMA were not significantly different between the preoperative period and final follow-up. We found that PD for symptomatic ANs in skeletally immature children was effective treatment, and some radiographic parameters showed significant differences between the preoperative period and final follow-up.

Disseminated gonococcal infection of the shoulder mimicking rheumatoid arthritis.

Introduction: Gonococcal arthritis is a characteristic of disseminated gonococcal infection (DGI). DGI arthritis is one of the most serious orthopedic emergencies because it can result in rapidly progressive joint damage, but it is often difficult to diagnose. Delayed treatment can result in the development of osteomyelitis in the adjacent bone, similar to other types of bacterial arthritis. Method: We report a case of gonococcal osteomyelitis associated with DGI that was initially treated as rheumatoid arthritis. The diagnosis was confirmed by DNA testing of synovium collected during arthroscopic debridement. Results: Seven years after the initial consultation, there was no acute-phase reactant, the arthritic changes had improved over time and the range of motion had increased. DGI may be difficult to confirm, but it is one of the most important entities that should be differentiated in the treatment of arthritis. Conclusion: Clinicians need to keep in mind that blood and synovial fluid cultures often do not lead to a definitive diagnosis.

Pathophysiology of abnormal compensation ability of the subtalar joint in the varus knee.

BACKGROUND: In recent years, the involvement of the compensation ability of the subtalar joint in lower extremity alignment has been reported. We previously showed that hindfoot alignment angle (HAA) is an indicator of compensation ability of the subtalar joint. The abnormal compensation ability of the subtalar joint was defined by the mobility of the subtalar joint, and evaluation of the mobility of the subtalar joint may help to further clarify the pathophysiology of abnormal compensation ability of the subtalar joint. This study was performed to evaluate the mobility of the subtalar joint and clarify the pathophysiology of abnormal compensation ability of the subtalar joint in the varus knee. METHODS: Seventy-two knees of 72 patients aged ≥40 years with varus knee were included in this study. Preoperative radiographs were used for measurement of this study parameters. Based on our previous study, we defined HAA of ≥15.9°as abnormal compensation ability of the subtalar joint. The patients were divided into an abnormal group (A-group) and normal group (N-group). All measurement parameters were compared between the groups, and correlations between the HAA and each measurement parameter were analyzed. RESULTS: The weight-bearing hindfoot angle (WBHA) (p < 0.001) and non-weight-bearing hindfoot angle (non-WBHA) (p = 0.003), were significantly greater in the A-group than in the N-group. Conversely, the ratio of change in hindfoot alignment (p = 0.006), were significantly smaller in the A-group than in the N-group. The HAA was positively correlated with WBHA (r = 0.66) and non-WBHA (r = 0.43) and negatively correlated with the ratio of change in hindfoot alignment (r = -0.32). CONCLUSIONS: The pathophysiology of abnormal compensation ability of the subtalar joint in the varus knee is thought to involve a state of increased valgus of hindfoot alignment and an inability to move into normal hindfoot alignment. LEVEL OF EVIDENCE: Level Ⅲ, retrospective study.

Arthroscopic ankle arthrodesis in two alkaptonuria patients.

Alkaptonuria is a very rare disorder in which homogentisic acid accumulates due to a deficiency in the activity of homogentisic acid 1,2 dioxygenase. This deficiency results in deposition of a yellowish-brown pigment in connective tissue. Such deposition is termed 'ochronosis' and leads to deterioration in the formation and structure of proteoglycans in hyaline cartilage. These actions lead to fragmentation and rapid destructive arthritis. Often, ochronotic arthritis appears at 40-60 years of age, and many patients are treated symptomatically. Here, we report two patients (three ankles) with ochronotic arthritis who were treated with ankle arthrodesis. In all cases, the postoperative clinical score improved, but the time needed for fusion was prolonged and symptomatic subtalar arthropathy developed in the early postoperative period.