Desmoplastic fibroma in a child: a 9-year follow-up case report.

BACKGROUND: Desmoplastic fibroma is an extremely rare primary bone tumor. Its characteristic features include bone destruction accompanied by the formation of soft tissue masses. This condition predominantly affects individuals under the age of 30. Since its histology is similar to desmoid-type fibromatosis, an accurate diagnosis before operation is difficult. Desmoplastic fibroma is resistant to chemotherapy, and the efficacy of radiotherapy is uncertain. Surgical excision is preferred for treatment, but it entails high recurrence. Further, skeletal reconstruction post-surgery is challenging, especially in pediatric cases. CASE PRESENTATION: Nine years ago, a 14-year-old male patient presented with a 4-year history of progressive pain in his left wrist. Initially diagnosed as fibrous dysplasia by needle biopsy, the patient underwent tumor resection followed by free vascularized fibular proximal epiphyseal transfer for wrist reconstruction. However, a histological examination confirmed a diagnosis of desmoplastic fibroma. The patient achieved bone union and experienced a recurrence in the ipsilateral ulna 5 years later, accompanied by a wrist deformity. He underwent a second tumor resection and wrist arthrodesis in a single stage. The most recent annual follow-up was in September 2023; the patient had no recurrence and was satisfied with the surgery. CONCLUSIONS: Desmoplastic fibroma is difficult to diagnose and treat, and reconstruction surgery after tumor resection is challenging. Close follow-up by experienced surgeons may be beneficial for prognosis.

Intercalary allograft reconstruction following femoral tumour resection: mid- and long-term results and benefits of adding a vascularised fibula autograft.

PURPOSE: Bone healing in femoral reconstructions using intercalary allografts can be compromised in a tumour context. There is also a high revision rate for non-union, infection, and fractures in this context. The advantages and disadvantages of an associated vascularised fibula graft (VFG) are still a matter of debate. METHODS: In a multicentre study, we retrospectively analysed 46 allograft reconstructions, operated on between 1984 and 2017, of which 18 were associated with a VFG (VFG+) and 28 without (VFG-), with a minimum follow-up of 2 years. We determined the cumulative probability of bone union as well as the mid- and long-term revision risks for both categories by Kaplan-Meier survival analysis and a multivariate Cox model. We also compared the MSTS scores. RESULTS: Significant differences in favour of VFG+ reconstruction were observed in the survival analyses for the probability of bone union (log-rank, p = 0.017) and in mid- and long-term revisions (log-rank, p = 0.032). No significant difference was observed for the MSTS, with a mean MSTS of 27.6 in our overall cohort (p = 0.060). The multivariate Cox model confirmed that VFG+ was the main positive factor for bone union, and it identified irradiated allografts as a major risk factor for the occurrence of mid- and long-term revisions. CONCLUSION: Bone union was achieved earlier in both survival and Cox model analyses for the VFG+ group. It also reduced the mid- and long-term revision risk, except when an irradiated allograft was used. In case of a tumour, we thus recommend using VFG+ from a fresh-frozen allograft, as it appears to be a more reliable long-term option.

Wrist Reconstruction Using Free Vascularized Fibular Head Graft Following Intralesional Excision for Campanacci Grade 3 Giant Cell Tumors Involving the Articular Surface of the Distal Radius.

Reconstruction with a free vascularized fibular head graft after en bloc excision of a Campanacci grade 3 giant cell tumor of bone in the distal radius can effectively control local recurrence. However, it leads to the loss of wrist movement, subsequent radiocarpal subluxation, and an osteoarthritic change. Another treatment option for grade 3 lesions is intralesional excision and cementation, which preserves wrist movement but does not restore the articular surface. We report a case of wrist reconstruction using a free vascularized fibular head graft after the intralesional excision of a Campanacci grade 3 giant cell tumor of bone with invasion of the articular surface of the distal radius. In patients with this type of a lesion, wrist reconstruction using a free vascularized fibular head graft after intralesional excision can help prevent local tumor recurrence, restore the articular surface, and maintain movements of the wrist joint.

Masticatory performance in patients undergoing free fibula flap for mandible reconstruction.

BACKGROUND: To explore the masticatory performance in patients undergoing an osteo(cutaneous) free fibula (OFF) flap for mandible reconstruction by a prospective design. METHODS: A total of 56 patients who had undergone OFF flap reconstructions for mandibular reconstruction secondary to malignant (squamous cell carcinoma) or benign (ameloblastoma) tumor resection were prospectively enrolled. They were asked to complete the masticatory performance test by the weigh method and the chew domain of the University of Washington quality of life questionnaire (version 4) preoperatively and at 3, 6, and 12 months postoperatively. The pair nonparametric test was used to analyze the dynamic change of masticatory performance and subjective chew function. RESULTS: Fifty-one patients were included for analysis finally. The mean masticatory performance for patients with malignant tumors were 53.4% ± 10.3%, 36.4% ± 10.3%, 42.6% ± 9.6%, 52.8% ± 10.9%, and 53.1% ± 11.8% preoperatively, at 2 weeks, 3 months, 6 months, and 12 months postoperatively, respectively. Compared with the preoperative level, the masticatory performance had a significant reduction immediately after surgery (p < 0.001), followed by a return to the baseline level within three months. A similar trend was noted for those with benign tumors. The mean score of chew domain for patients with malignant tumors were 100 ± 0, 54.3 ± 32.9, 81.4 ± 24.5, and 92.9 ± 17.8 preoperatively, at 3 months, 6 months, and 12 months postoperatively, respectively. Compared with the preoperative level, the subjective chew function was greatly affected within the first three months (p < 0.001), and it gradually recovered to the baseline level in the following nine months. A similar trend was noted in patients with benign tumors. CONCLUSIONS: The masticatory performance and subjective chew function was significantly affected after OFF flap reconstructions in the short term, but both recovered to the preoperative levels within 9-12 months.

Identification of EWSR1-NFATC2 fusion in simple bone cysts.

AIMS: Simple bone cysts are benign intramedullary tumours primarily involving the long bones in skeletally immature individuals. Several mechanisms have been proposed for their pathogenesis. Although the diagnosis is typically straightforward, the interpretation can be problematic, because of superimposed fracture causing them to resemble aneurysmal bone cysts and other tumours. EWSR1-NFATC2 or FUS-NFATC2 fusions, which are characteristic of a subset of aggressive round cell sarcomas, have been recently detected in simple bone cysts. The aim of this study was to examine the clinicopathological and molecular features in a series of simple bone cysts. METHODS AND RESULTS: Using RNA-based next-generation sequencing and/or fluorescence in-situ hybridisation, we investigated the presence of EWSR1 or FUS rearrangements in nine simple bone cysts. The patients were five females and four males, aged 3-23 years (median, 14 years); the tumours ranged from 19 mm to 160 mm (median, 46 mm) in size, and involved the femur (n = 3), humerus (n = 2), fibula (n = 2), tibia (n = 1), and iliac wing (n =1). We identified three cases with EWSR1-NFATC2 fusion (showing identical breakpoints to those in EWSR1-NFATC2 sarcomas) and one additional case with FUS rearrangement. Unlike in EWSR1-NFATC2 sarcomas, immunohistochemical expression of NKX3.1 and NKX2.2 was absent in two simple bone cysts tested. CONCLUSIONS: More than 40% of simple bone cysts harbour genetic alterations confirming that they are neoplastic, investigation of EWSR1 and/or FUS rearrangement may help to distinguish simple bone cysts from mimics, and NFATC2 rearrangement is not pathognomonic of malignancy.

Peroneal Nerve Function Before and Following Surgical Excision of a Proximal Fibular Osteochondroma.

BACKGROUND: Osteochondromas occur most commonly in the distal femur, proximal tibia, and humerus. There are no large studies reviewing the outcome of treatment for patients with an osteochondroma involving the proximal fibula. The purpose of this study is to specifically understand the manifestations of a proximal fibular osteochondroma (PFO) on the preoperative peroneal nerve function, and how surgical management of the osteochondroma affects function immediately postoperatively and at long-term follow-up. METHODS: This is an institutional review board-approved retrospective review of a consecutive series of patients with a PFO treated operatively at a single institution. The medical record was carefully reviewed to identify demographic data, clinical data especially the status of the peroneal function at various time points. RESULTS: There were 25 patients with 31 affected extremities who underwent surgical excision of the PFO at an average age of 12.4 years (range, 3.0 to 17.9 y). There were 16 males and 9 females. The underlying diagnosis was isolated PFO in 2 (8%) patients and multiple hereditary exostosis in 23 (92%) patients. Preoperatively, 9 (29%) had a foot drop and 22 (71%) did not. Those with a preoperative foot drop underwent surgery at a younger age (9.1 vs. 13.8 y) (P<0.004) and postoperatively 5 (55.5%) had complete resolution, 3 (33.3%) had improvement, and 1 (11.1%) persisted requiring an ankle foot orthosis. Of the 22 who were normal preoperatively, 5 (22.7%) developed an immediate postoperative foot drop, 3 (60%) completely resolved, 1 (20%) improved, and 1 (20%) persisted and was found to have a transected nerve at exploration. In total, 23 of the 25 (92%) patients who had a PFO excision, had a normal or near-normal peroneal nerve function including those who had poor function preoperatively. CONCLUSIONS: Patients with a PFO have a preoperative peroneal nerve dysfunction 30% of the time and 23% of those who were normal preoperatively have postoperative dysfunction. Fortunately, nearly all patients have a complete recovery following excision of the osteochondroma. LEVEL OF EVIDENCE: Level IV.

Diagnosis of avulsion fractures of the distal fibula after lateral ankle sprain in children: a diagnostic accuracy study comparing ultrasonography with radiography.

BACKGROUND: The purpose of this study was to determine the diagnostic accuracy of ultrasonography for the diagnosis of avulsion fractures of the distal fibula for lateral ankle sprain in children and compare it to that of radiography. METHODS: Children who sustained lateral ankle sprain were prospectively surveyed. They underwent both ultrasonography and radiography at the first clinic visit to diagnose any concomitant avulsion fractures of the distal fibula. The patients underwent follow-up radiography 4 weeks later to obtain the reference standard diagnosis. The measures of diagnostic accuracy (i.e., sensitivity, specificity, positive predictive value, and negative predictive value) of the initial ultrasonography and radiography were calculated; they were then compared using the McNemar test. Totally, 52 patients (with a median age of 9 years) were analyzed. RESULTS: On the reference standard (follow-up) radiographs, 32 patients (62%) were found to have avulsion fractures of the distal fibula. The sensitivity, specificity, positive predictive value, and negative predictive value for ultrasonography were 94, 85, 91, and 89% respectively; and 81, 100, 100, and 77% respectively for radiography at the first visit. There were no significant differences in sensitivity and specificity between the two diagnostic methods (P = 0.22, 0.25). CONCLUSIONS: Ultrasonography has a high diagnostic accuracy, which is comparable to that of radiography, for the diagnosis of avulsion fracture of the distal fibula. Ultrasonography may be used as an option of imaging modality for lateral ankle sprain in children.

Type VII All-epiphyseal Fractures of the Lateral Malleolus and the Origin of Subfibular Ossicles.

BACKGROUND: A subfibular ossicle (SO), also known as an os subfibulare, is present in ∼1% of the general population. Two theories have been proposed to explain the origin of SOs: (1) as a failure of fusion of a secondary center of ossification; (2) as a posttraumatic sequela. This report offers prospective, longitudinal radiographic evidence for the formation of SOs as a posttraumatic sequela of type VII transepiphyseal fractures of the lateral malleolus in children. METHODS: This Institutional Review Board-approved study was performed at a tertiary care pediatric hospital from March 2012 to April 2019. The study group included 37 children with a type VII fracture of the lateral malleolus and a minimum follow-up of 6 months. RESULTS: Twenty-one children (57%) healed their fracture. Sixteen children (43%) went on to form SOs. The most common location for the fractures was the distal third of the epiphysis, and the most common fracture type forming SOs was a sleeve avulsion fracture. Four of the children forming SOs have had surgery to address pain and recurrent sprains. CONCLUSIONS: Overall, 43% of children who sustained a type VII fracture of the lateral malleolus went on to form SOs, giving support to the posttraumatic theory of origin. Sleeve avulsion fractures have the greatest chance of forming SOs. So far, 4 of the 16 children forming SOs have undergone surgery for ankle pain and recurrent sprains. LEVEL OF EVIDENCE: Level II.

Successful Treatment of Relapsed Isolated Extraocular Retinoblastoma in the Right Fibula With High-dose Chemotherapy and Autologous Stem Cell Transplantation.

Literature on high-dose chemotherapy followed by autologous stem cell rescue in relapsed retinoblastoma is limited to <150 cases reported so far. We present our experience and the challenges faced in the management of a 7-year-old boy with relapsed isolated extraocular retinoblastoma in the right fibula who received salvage chemotherapy followed by high-dose chemotherapy and autologous stem cell rescue. Electrolyte disturbances, renal tubulopathy, and seizures were the most significant transplant-related morbidity. The child is now 3 years postautograft in remission. Monitoring for second malignant neoplasm and late side effects remain the main challenges in the years to come.

A Rare Case of Tibioperoneal Arterial Trunk Entrapment Caused by a Fibular Osteochondroma.

BACKGROUND: Osteochondromas or exostoses are the most common benign tumors of the bones, which appear during the growth period. The involvement of lower extremities is common, particularly in metaphyseal structures of the femur and humerus and around the knee joint. However, the incidence of the development of the tumor at the proximal fibula is rare. The most common signs and symptoms of the disease are pain, pulsatile mass, limb swelling, neurologic sequelae, bursa formation with subsequent bursitis, and impairment of the developmental growth. Vascular complications are rare, yet osteochondromas can cause catastrophic arterial complications threatening the life of the patient if they occur and can include vessel perforation and thrombosis, arterial thromboembolic events, and pseudoaneurysm formation. METHODS: We report a case of a 24-year-old male patient presenting with tibioperoneal arterial trunk entrapment caused by a massive osteochondroma derived from the proximal fibula. A combined vascular-orthopedic approach was initiated with the excision of the tumor, in which the neurovascular structures (tibial nerve, popliteal artery and vein, anterior tibial artery, and tibioperoneal trunk) were carefully recognized and protected. RESULTS: The postoperative course of the patient was uneventful. CONCLUSIONS: High clinical suspicion of a vascular complication should be raised by physicians when investigating a young patient with a suspected osseous tumor in the popliteal fossa and symptomatology of concurrent peripheral arterial disease. Prompt surgical management is crucial for the salvage of the affected limb in cases of arterial involvement. Furthermore, quick surgical exposure of the mass and regular postoperative follow-up check minimizes the risk of irreparable impairments and tumor recurrence.

Computed Tomography Analysis for Quantification of Displacement of the Distal Fibula in Different Foot Positions With Weightbearing and Sequentially Increased Instability: An Anatomic Cadaveric Study on Syndesmosis.

Syndesmotic injuries are quite common, but accurate diagnosis and treatment can be difficult, in part because of individual anatomic variation and complex movements of the fibula in the incisura. The current cadaveric study was designed to investigate changes in the position of the fibula in the incisura during simulated weightbearing in different foot positions and with sequential sectioning of syndesmotic and deltoid ligaments. Sixteen paired, fresh-frozen cadaveric limbs were embedded in polymethylmethacrylate mid-calf and placed in a weightbearing simulation frame. Computed tomography scans were obtained while the legs were in a simulated foot-flat position (75 N) and single-leg stance (700 N) in 5 foot positions: neutral, 15° external rotation, 15° internal rotation, 20° dorsiflexion, and 20° plantar flexion. The anterior-inferior tibiofibular ligament, posterior tibiofibular ligament complex, deltoid, and interosseous membranes were sectioned sequentially and rescanned. Measurements of fibular diastasis, rotation, anterior-posterior and medial-lateral translation, and fibular shortening were performed. The most destructive state resulted in the largest displacement at the syndesmosis. The degree of subluxation in all ligament states was dependent on the foot position. External rotation created statistically significant displacement at all levels of injury. There were no significant differences between sides of the same donor. Our data demonstrate the importance of foot position in reduction at the syndesmosis under weightbearing. The current ex vivo model could be used to evaluate other aspects of this injury or the value of reconstructive techniques in the future.

Detecting stress injury (fatigue fracture) in fibular cortical bone using quantitative ultrashort echo time-magnetization transfer (UTE-MT): An ex vivo study.

Bone stress injury (BSI) incidents have been increasing amongst athletes in recent years as a result of more intense sporting activities. Cortical bone in the tibia and fibula is one of the most common BSI sites. Nowadays, clinical magnetic resonance imaging (MRI) is the recommended technique for BSI diagnosis at an early stage. However, clinical MRI focuses on edema observations in surrounding soft tissues, rather than the injured components of the bone. Specifically, both normal and injured bone are invisible in conventional clinical MRI. In contrast, ultrashort echo time (UTE)-MRI is able to detect the rapidly decaying signal from the bone. This study aimed to employ UTE-MRI for fatigue fracture detection in fibula cortical bone through an ex vivo investigation. Fourteen human fibular samples (47 ± 20 years old, four women) were subjected to cyclic loading on a four-point bending setup. The loading was displacement controlled to induce -5000 ± 1500 µ-strain at 4 Hz. Loading was stopped when bone stiffness was reduced by 20%. Fibula samples were imaged twice, using UTE-MRI and micro-computed tomography (µCT), first pre-loading and second post-loading. After loading, the macromolecular fraction (MMF) from UTE-MT modeling demonstrated a significant decrease (12% ± 20%, P = 0.02) on average. Single-component T2 * also decreased significantly by BSI (12% ± 11%, P = 0.01) on average. MMF reduction is hypothesized to be a result of collagenous matrix rupture and water increase. However, faster T2 * decay might be a result of water shifts towards newly developed microcracks with higher susceptibility. Despite this good sensitivity level of the UTE-MRI technique, the µCT-based porosity at a voxel size of 9 µm was not affected by loading. UTE-MRI shows promise as a new quantitative technique to detect BSI.

Comparison of clinical features, management and outcomes of osteosarcoma located in proximal fibula and proximal tibia: a propensity score matching analysis.

BACKGROUND: The aim of this study was to compare proximal fibular and proximal tibial sites regarding osteosarcoma in the proximal crus. Furthermore, we proposed a hypothesis explaining the differences. METHODS: From Jaunary 2000 to February 2015, 28 patients with non-metastatic proximal fibular osteosarcoma and 214 patients with non-metastatic proximal tibial osteosarcoma underwent surgery were identified in our center. All clinical data were analyzed retrospectively. Propensity score matching of patients in a 1:2 ratio was conducted based on age, gender and Enneking stage. To analyze possible factors resulting in amputation, we investigated extraosseous tumor volumes (ETVS), the nearest of the blood vessel to reactive zone (NBR) and the nearest of the blood vessel to tumor (NBT). RESULTS: Amputation rates were higher in the proximal fibula cohort (35.7%) than in the proximal tibia cohort (14.3%; p = 0.046). Comparing possible clinical characteristics related with amputation between two cohorts, the proximal fibula cohort had larger ETVS (p = 0.000). Moreover, the proximal fibula cohort had a smaller NBT for anterior tibial vessels (p = 0.025), a smaller NBR for posterior tibial vessels (p = 0.013) and a smaller NBT for posterior tibial vessels (p = 0.007) than the proximal tibia cohort. Univarite and multivariable analyses showed that NBT for posterior tibial vessels was the only independent factor associated with amputation. The 3-year event-free survival (EFS) and overall survival (OS) rates for the proximal fibula cohort vs. the proximal tibia cohort were 52.6% vs. 78.0% (p = 0.045) and 63.7% vs. 81.2% (p = 0.177), respectively. The MSTS scores for the functional evaluation of limb-salvaging surgery were similar in both groups (p = 0.212). CONCLUSIONS: Amputation rates among patients were higher when osteosarcoma was located in proximal fibula than in proximal tibia. A smaller NBT for posterior tibial vessels was associated with higher amputation rates. Prognosis of the proximal fibula cohort was poorer than that of the proximal tibia cohort of osteosarcoma patients.

Effects of locally administered rhBMP-2 and bisphosphonate on bone regeneration in the rat fibula.

OBJECTIVE: To evaluate the ability of xenogenic bone and absorbable collagen sponge to function as an rhBMP-2 carrier and the osteoinductivity of bisphosphonate by comparison with recombinant human bone morphogenetic protein-2 (rhBMP-2). MATERIALS AND METHODS: Thirty-two Sprague-Dawley male rats were divided into four groups. Segmental ostectomy of both fibulae was performed, and the defect area was then treated with Rapiderm Pad (absorbable collagen sponge; COL_BMP) or CollaOss (xenogenic bone; XENO_BMP) with application of rhBMP-2. Alternatively, both fibulae were grafted with xenogenic bone with different bisphosphonate concentrations (XENO_Low BP, XENO_High BP). After 4 or 8 weeks, animals were sacrificed, and radiographic, histological, histomorphometric, and immunohistochemical analyses were performed. RESULTS: Recombinant human bone morphogenetic protein-2 promoted bone formation, regardless of the carrier, and exhibited continuity between the graft material and defect area. Moreover, the results showed that higher concentrations of bisphosphonate were associated with greater bone formation than lower concentrations of bisphosphonate. CONCLUSION: Absorbable collagen sponges with rhBMP-2 were advantageous in that there was no remaining graft material and that the bone was remodeled to resemble the existing fibula. The local application of bisphosphonate promoted new bone formation, particularly when used at high concentrations. High-concentration bisphosphonate induced new bone formation comparable to rhBMP-2 with lesser remaining bone material.

Is double-approach surgery and tenodesis without a gastrocnemius flap better for dealing with proximal fibular osteosarcoma?

BACKGROUND: Resection of proximal fibular osteosarcoma involving the posteromedial aspect of the fibula is challenging. Reconstruction using a gastrocnemius flap may result in significant lateral instability and abnormal knee movement. Furthermore, postoperative gait may be disturbed by foot drop resulting from scarification of the common peroneal nerve. METHODS: Between January 2011 and December 2013, five patients with proximal fibular osteosarcoma were treated via the double-approach procedure using en bloc resection without a gastrocnemius flap. Simultaneously, all patients received one-stage tenodesis of the anterior tibial and toe extensor tendons. Clinical outcomes, including local tumor recurrence, complications, and functional outcomes, were evaluated. RESULTS: The mean follow-up duration was 47.2 months (range 42-52 months). No patients experienced local recurrence. The patients' Enneking functional scores were excellent (80%) or good (20%) at the final follow-up. CONCLUSIONS: In patients with proximal fibular osteosarcoma, the double-approach procedure allows easier and safer en bloc tumor resection with vessel and nerve protection. One-stage tenodesis without a gastrocnemius flap is associated with good functional outcomes.

Residual bone fragments in tibiofibular joint and postoperative local recurrence: an analysis of 21 cases of proximal fibular giant cell tumour.

BACKGROUND: Currently, there are no known reports on the aetiology of local giant cell tumour (GCT) recurrence in the proximal fibula following en bloc resection. We analysed 21 cases of proximal fibular GCT, focusing on the presence of residual bone in the tibiofibular joint, its causes and its impact on postoperative recurrence. METHODS: We retrospectively analysed 21 cases with proximal fibular GCT occurring between 2000 and 2017. RESULTS: There were 14 males and 7 females. The average patient age was 25.0 years. Seventeen patients were diagnosed and treated at our facility, while 4 were referred after local recurrence. Six patients presented with residual bone fragments in the tibiofibular joint during their first month of follow-up. Patients with residual bone fragments had a higher local recurrence rate (83.3%) than those without (0%, p = 0.0003). Upon further analysis, patients with a preoperative Campanacci grade III tumour (p = 0.0055) and pathological fractures (p = 0.0109) were at a higher risk of exhibiting postoperative residual bone fragments. CONCLUSIONS: The presence of residual bone fragments in the tibiofibular joint was the main cause of postoperative local recurrence. The presence of residual bone fragments may be related to the preoperative Campanacci grade and pathological fractures. Therefore, close attention should be paid to postoperative follow-up examinations, and if recurrence is suspected, surgical resection should be planned.

Prediction Models to Improve the Diagnostic Value of Plain Radiographs in Children With Complete Discoid Lateral Meniscus.

PURPOSE: To develop prediction models to improve the diagnostic utility of plain radiographs for the diagnosis of complete discoid lateral meniscus by combining previously reported radiographic findings. METHODS: Patients ages 5 to 16 years with complete discoid lateral meniscus confirmed by arthroscopy or magnetic resonance imaging were included. Patients with insufficient radiographs were excluded. Normal control subjects were randomly sampled by age and sex matching. Subjects were divided into 2 groups considering skeletal maturation (5-9 and 10-16 years). Radiographic variables included were lateral joint space, height of the fibular head, height of the lateral tibial spine, obliquity and cupping of the lateral tibial plateau, condylar cutoff sign, and squaring and notching of the lateral femoral condyle. Prediction models were developed by regression analyses. The cutoff value (COV) for best accuracy was determined with its sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). RESULTS: A total of 162 knees (126 patients) with complete discoid lateral meniscus and 151 age- and sex-matched knees (151 subjects) with normal meniscus were included. In subjects 5 to 9 years old, the prediction model was risk score = [-20.08 * height of the fibular head/femoral interepicondylar distance (FIED)] + [-42.26 * height of the lateral tibial spine/FIED]. The COV of -8.47 showed the best accuracy (74.4%), with sensitivity of 85.9%; specificity, 60.4%; PPV, 72.4%; and NPV, 78.0%. In subjects 10 to 16 years old, the prediction model was risk score = [77.04 * lateral joint space/FIED] + [-34.55 * height of the fibular head/FIED] + [-56.58 * height of the lateral tibial spine/FIED] + [-16.44 * condylar cutoff sign]. The COV of -18.03 showed the best accuracy (85.4%), with sensitivity of 79.6%; specificity, 90.4%; PPV, 87.6%; and NPV, 83.9%. CONCLUSIONS: The prediction models combining the plain radiographic findings showed higher diagnostic values than the diagnostic values of the individual radiographic findings. The results of this study provide improved diagnostic utility of plain radiography for the detection of completed discoid lateral meniscus in children. LEVEL OF EVIDENCE: Level III, diagnostic study.

Transepiphyseal (Type VII) Ankle Fracture Versus Os Subfibulare in Pediatric Ankle Injuries.

BACKGROUND: Pediatric ankle injuries are common, giving rise to ∼17% of all physeal injuries. An os subfibulare in a child with an ankle sprain may be confused with a type VII transepiphyseal fracture. Here, we evaluate the clinical and radiographic features of type VII transepiphyseal fractures to those of os subfibulare presenting with acute ankle trauma with the hypothesis that radiographs are necessary for final diagnosis and neither clinical history nor examination would be diagnostic. METHODS: We performed an internal review board-approved, retrospective chart review of patients identified with a traumatic os subfibulare or type VII ankle fracture over an 18-month period. Charts were reviewed for demographics, mechanism, and clinical findings on initial presentation. Radiographic measurements of the distal fibular fragment as well as epiphysis were made on presenting ankle series radiographs. RESULTS: A total of 23 patients were identified. Eleven patients had a traumatic type VII ankle fracture and 12 had trauma associated with an os subfibulare on initial radiographs. The history and clinical presentations were similar and were nondiagnostic. The ratio of the width of the fibula at its largest point on the anterior posterior view to the width of the fibular fragment was significantly larger in the type VII ankle fractures (P=0.05). All os subfibulare were located within the inferior third of the epiphysis, whereas all type VII fractures were either at the equator or within the middle third of the fibular epiphysis. CONCLUSIONS: Radiographs, not clinical presentation, can differentiate an os subfibulare from a type VII transepiphyseal fracture. Children with type VII fractures have a long, irregular fracture line within the middle third of the distal fibular epiphysis. Those with an ankle sprain and os subfibulare have a smooth-edged ossicle of relatively short length located within the inferior pole of the epiphysis. Furthermore, the radiographic width of the fragment in the type VII fractures is significantly larger in width than the os subfibulare. LEVEL OF EVIDENCE: Level II.

Associations between proximal tibiofibular joint (PTFJ) types and knee osteoarthritic changes in older adults.

PURPOSE: To describe the cross-sectional associations between proximal tibiofibular joint (PTFJ) type configurations and knee joint structural abnormalities in older adults. METHODS: A total of 967 community-based participants were studied. T1-weighted fat-suppressed magnetic resonance image (MRI) with spoiled gradient recalled echo sequence was utilized to assess the PTFJ type configurations. Knee cartilage volume, cartilage defects, bone marrow lesions and osteophytes were measured. Linear regression and binary logistic regression analyses were used to examine the associations between PTFJ type configurations and knee joint cartilage volume as well as knee structural abnormalities, respectively, after adjustment for potential confounders. RESULTS: Seven PTFJ types including plane (49.4%), trochoid (31.9%), double trochoid (4.3%), saddle (5.4%), condylar (5.3%), trochlear (3.5%) and ball & socket (0.2%) were observed. Plane type was used as the comparator. In multivariable analyses, irregular joint types (comprising the five uncommon joint types) were associated negatively with cartilage volume, and positively with knee cartilage defects, bone marrow lesions and osteophytes in the lateral (but not medial) compartments. In contrast, trochoid type was only associated with reduced femoral cartilage volume, but not with knee cartilage defects, bone marrow lesions and osteophytes. CONCLUSIONS: Irregular PTFJ joint shapes are associated with osteoarthritic changes in the lateral, but not medial, tibiofemoral compartment in older adults. The causal relationship needs to be examined in future longitudinal studies.

Microsurgical Reconstruction Following Oncologic Resection in Pediatric Patients: A 15-Year Experience.

BACKGROUND: Free tissue transfer in the pediatric population is a challenging endeavor, even for experienced microsurgeons. Some surgeons argue these cases can be limited by vessel size and spasticity and should be undertaken only when absolutely necessary. We present a 15-year experience examining outcomes of free tissue transfer in pediatric oncologic patients. METHODS: All free flaps performed at a single institution in pediatric patients (age range 3-17) between January 2000 and December 2014 were reviewed. RESULTS: Overall, 102 patients (mean age 12.1 ± 4.0 years) were identified who underwent 109 free flaps. The most common flaps were the fibula free flap (46%) and the anterolateral thigh free flap (27%). 81 cases (74%) had malignant disease with 70 cases (64%) involving the head and neck region. 21 cases (19%) had preoperative radiation and 58 cases (53%) had preoperative chemotherapy. 5 cases had total flap loss (4.6%) and 17 cases (15.6%) had immediate post-operative complications, with wound infection (4.6%) being most common. 17 cases (15.6%) had long-term complications with delayed or non-union (4.6%) being most common. Survival rate was 91.7% at 1 year and 78.9% at 5 years. CONCLUSIONS: Free tissue transfer is a reliable and appropriate choice in pediatric patients requiring soft tissue or bony reconstruction. Even in pediatric oncologic patients with preoperative chemotherapy or radiation, flap survival and outcomes are comparable to the adult population. Pediatric free tissue transfer should not be avoided but instead considered the gold standard for patients with complex defects, just as it is in the adult population.