Long-term Results of the Thrust Plate Prosthesis, 21-year Follow-up: A Case Report and Literature Review

Introduction: The thrust plate prosthesis (TPP) is a type of cementless hip replacement. Aimed to preserve femoral diaphyseal bone, it was favored by some orthopedic surgeons in younger patients as they could potentially undergo multiple revision arthroplasties during their lifetime. Of particular note, the preserved diaphyseal bone allows for the implantation of a subsequent primary total hip arthroplasty (THA). Case Report: We reported on a 64-year-old male patient who underwent thrust plate prosthesis (TPP) implantation 21 years ago (1999) for the treatment of primary osteoarthritis (OA) of the right hip joint. At 21-year follow-up, he had not developed any post-operative complications, and he reported a SF12 score of 32 and Oxford hip score of 47/48. Conclusion: TPP proved to be successful clinically and radiologically, especially in the young patient. It loads directly to the cortex of the proximal femoral metaphysis as in a native hip joint. It is a bone preserving prosthesis which allows for good bone stock in the case of revision surgery that was a victim of commercial considerations. Keywords: Thrust plate prosthesis, thrust plate prosthesis, arthroplasty.

The path to minimizing instability in developmental dysplasia of the hip: is Capsulorrhaphy a necessity or a futile habit?

Background To evaluate and quantify the intraoperative effect of capsulorrhaphy on the deep seating of femoral head within the acetabulum as measured by medial joint space, a surrogate measure of acetabular-head contact. Methods In order to determine the exact effect of capsulorrhaphy, we prospectively scrutinized a consecutive sample of 18 patients with unilateral dysplastic hips aging > 18 months and followed them for a period of at least 12 months. The procedure of open reduction is described in detail. Two pediatric orthopedists carried out the operations from August 2014 to January 2019 at a tertiary pediatric hospital. Intraoperatively, AP radiographs of the pelvis were obtained before and after capsulorrhaphy. The distance between the inferomedial edge of the proximal femoral metaphysis and the lateral edge of the obturator foramen was recorded. To determine if there were differences in medial joint space due to capsulorrhaphy, a generalized linear model was run on the study sample. All patients were followed for at least 12 months to determine the rate of re-dislocation. Results Mean age (±standard deviation) of the participants was 37.5 (±24.7) months. All cases underwent Salter osteotomy, 5 cases needed femoral shortening (27.8%) and none needed derotational osteotomy. Capsulorrhaphy lead to a statistically significant decrease in the mean medial joint space from 1.59 cm before (95% CI: 1.12–2.05) to 0.76 cm after (95% CI: 0.50–1.02) the capsulorrhaphy (P < 0.001). When we took the effect of age into account the corresponding figures were 1.47 (95% CI: 1.22–1.75) and 0.67 (95% CI: 0.39–0.94), respectively (P < 0.001). After follow up periods of 1 to 5.5 years, none of the patients experienced instability or re-dislocation. Conclusions Capsulorrhaphy, independently, of age was associated with a 1-cm decrease in the mean medial hip joint space and a more deeply seated femoral head. Furthermore, this study presents a successful experience with capsulorrhaphy to prevent hip instability.

Outcome analysis of solitary osteochondromas of femur managed surgically: a series of 32 patients

<p class="abstract"><strong>Background:</strong> Osteochondroma is the commonest benign bone tumor in humans. This tumor may either be solitary or present as multiple lesions. Solitary osteochondromas are much more common. Femur is the single most common long bone involved followed by tibia and humerus. Osteochondromas may be either asymptomatic or may present as pain, pressure symptoms or functional impairment. Most of the symptomatic lesions need surgical excision.</p><p class="abstract"><strong>Methods:</strong> This was a prospective study which included 32 patients with solitary osteochondromas of femur, who were managed with surgical excision. Only the symptomatic cases were operated. Minimum follow-up period was 18 months after surgery.<strong></strong></p><p class="abstract"><strong>Results:</strong> This study involved 23 males (71.87%) and nine females (28.12%). 30 osteochondromas (93.75%) were located in the distal femoral metaphysis while as only two cases (6.25%) of proximal metaphyseal involvement were seen. The commonest indication for surgery was pain. Other indications included cosmetic causes, restricted joint movement, fracture of osteochondroma and paresthesia or numbness. The complications included post-operative hematoma formation which was seen in 2 patients (6.25%), infection which was seen in one patient (3.12%), post-operative hypoaesthesia in 2 patients (6.25%) and recurrence of the tumor occurred in one patient (3.12%).</p><p><strong>Conclusions:</strong> Surgical excision of the solitary symptomatic femoral osteochondromas is a rewarding and safe procedure with minimal complications. </p>

Extra Axial Chordoma of the Distal Femoral Metaphysis: A Case Report

Background Chordomas are malignant bone tumors that are derived from remnant embryonic tissue of the notochord and are typically found in the axial midline. When they are found outside of the axial skeleton, the diagnosis can be challenging and elusive. Often, they are overlooked on initial presentation in lieu of other more common lesions, including cartilage tumors (eg, enchondroma, chondrosarcoma, osteochondromatosis) due to their overlapping features. Case Report A 30-year-old female with a four-year history of intermittent left knee pain presented for initial evaluation. Physical exam of the knee was unremarkable except for moderate tenderness on palpation. Radiographs showed a lucent lesion with peripheral sclerosis, eccentrically located within the anteromedial femoral diaphysis. The patient was subsequently lost to follow-up. She presented again two years later with similar symptoms. Her physical exam remained unchanged, and repeat radiographs showed interval growth. She underwent open biopsy of the left distal femur, with pathology revealing tumor consisting predominantly of epithelioid cells set in an abundant myxoid matrix. Immunohistology showed cells that stained strongly for EMA, CK19, and brachyury. These findings support the diagnosis of extra-axial chordoma. Discussion Extra-axial chordomas remain a challenging diagnosis for clinicians due to their extreme rarity and overlapping features with other more common lesions. They are often misdiagnosed as extraskeletal myxoid chondrosarcomas or myoepitheliomas. Our patient’s insidious presentation and radiologic findings present a learning opportunity for clinicians to recognize extra-axial chordomas as a potential early diagnosis in someone presenting with a long history of intermittent and worsening knee pain.

Prognostic value of severity of dislocation in late-detected developmental dysplasia of the hip

Purpose The aims of this study were to evaluate the reliability of three classifications of severity of dislocation in late-detected developmental dysplasia of the hip (DDH), especially to assess whether they are predictive of long-term outcomes. Methods Two groups of patients were analyzed. Group 1 (57 patients, 69 hips) underwent closed reduction between 1958 and 1962. Mean age at reduction was 20.3 months (4 to 65). Group 2 (50 patients, 54 hips) treated between 1996 and 2005, was used for analysis of the association between severity of dislocation and treatment (open or closed reduction). The primary radiographs were graded according to the Tönnis classification, the classification of the International Hip Dysplasia Institute and a new method based on the position of the most lateral point of the proximal femoral metaphysis (lateral metaphysis height classification, LMH). The outcome at a mean age of 51.2 years (55 to 60) was graded according to the occurrence of osteoarthritis (OA) and total hip arthroplasty (THA). Results There were significant associations between the classifications, and the intra- and interobserver agreements were high. More severe grades of DDH were significantly associated with age ≥ 18 months and with open reduction. None of the classifications were significantly associated with long-term OA. The LMH method was significantly associated with the need for THA, whereas the other classifications were not. Conclusion All the classifications were reliable in grading severity of DDH. The LMH method seems preferable in clinical practice because the main landmarks were easy to define and because it had long-term prognostic value. Level of Evidence III

SUN-350 Bone Marrow Adipose Tissue Is Associated with Fracture Prevalence in Anorexia Nervosa

Anorexia nervosa, a psychiatric disorder predominantly affecting women, is characterized by self-induced starvation, low body weight, low subcutaneous and visceral fat depots, and low bone mass. More than 85% of women with anorexia nervosa have bone mineral density (BMD) values more than one standard deviation below the mean of women of comparable age. Although there is a significantly increased risk of fracture in women with anorexia nervosa, low BMD has not been shown to consistently predict the increased fracture rate in this population. Despite low subcutaneous and visceral adipose tissue stores, women with anorexia nervosa have increased bone marrow adiposity, which is inversely associated with BMD. We hypothesized that increased bone marrow adipose tissue would be associated with the increased fracture rate in women with anorexia nervosa. We studied sixty-two women: 34 with anorexia nervosa (mean age + SEM: 28.3 + 0.9 years) and 28 normal-weight controls of similar age (28.3 + 1.1 years; p=0.72). We examined associations between lifetime self-reported fracture history and 1) BMD of the lumbar spine (L1-L4), lateral spine (L2-L4), total hip, and femoral neck measured by dual energy X-ray absorptiometry and 2) bone marrow adipose tissue at the spine (L4 vertebra) and hip (femoral metaphysis, diaphysis and epiphysis) measured by 1H-magnetic resonance spectroscopy. Women with anorexia nervosa had significantly lower BMD at the spine and hip (p&lt;0.0001 at all sites) and significantly higher bone marrow adipose tissue at the L4 vertebra (p&lt;0.0001) and femoral metaphysis (p=0.001) as compared to normal-weight controls. Forty-seven percent (n=16) of women with anorexia nervosa versus 39% (n=11) of normal-weight controls reported a lifetime history of fracture (p=0.54). In women with anorexia nervosa, there was no significant association between fracture history and BMD at the spine or hip (p=0.27-0.98). In the group as a whole, bone marrow adipose tissue was greater in the L4 vertebra in individuals with a history of fracture compared to those without a fracture history (p=0.02). In subjects with anorexia nervosa, those with a history of fracture had greater bone marrow adipose tissue at the L4 vertebra (p=0.01) and femoral diaphysis (p=0.01) compared to those without a history of fracture; these differences in bone marrow adipose tissue remained significant after controlling for BMI (p=0.01-0.03) and also after controlling for BMD (p&lt;0.01 for both). Higher bone marrow adipose tissue is associated with increased fracture prevalence and may be a better predictor of fracture risk than BMD in women with anorexia nervosa. Future prospective studies will be necessary to better understand the association between bone marrow adiposity and fracture risk in this population.

Different effects of Wnt/β-catenin activation and PTH activation in adult and aged male mice metaphyseal fracture healing

Background: Fractures in older men are not uncommon and need to be healed as soon as possible to avoid related complications. Anti-osteoporotic drugs targeting Wnt/β-catenin and PTH (parathyroid hormone) to promote fracture healing have become an important direction in recent years. The study is to observe whether there is a difference in adult and aged situations by activating two signal paths. Methods: A single cortical hole with a diameter of 0.6 mm was made in the femoral metaphysis of Catnb lox(ex3) mice and wild-type mice. The fracture healing effects of CA (Wnt/β-catenin activation) and PTH (activated by PTH (1–34) injections) were assessed by X-ray and CT imaging on days 7, 14, and 21 after fracture. The mRNA levels of β-catenin, PTH1R( Parathyroid hormone 1 receptor ), and RUNX2(Runt-related transcription factor 2) in the fracture defect area were detected using RT-PCR. Angiogenesis and osteoblasts were observed by immunohistochemistry and osteoclasts were observed by TRAP (Tartrate-resistant Acid Phosphatase). Result: Adult CA mice and adult PTH mice showed slightly better fracture healing than adult wild-type (WT) mice, but there was no statistical difference. Aged CA mice showed better promotion of angiogenesis and osteoblasts and better fracture healing than aged PTH mice. Conclusion: The application of Wnt/β-catenin signaling pathway drugs for fracture healing in elderly patients may bring better early effects than PTH signaling pathway drugs, but the long-term effects need to be observed.

Different effects of Wnt/β-catenin activation and PTH activation in adult and aged male mice metaphyseal fracture healing

Background: Fractures in older men are not uncommon and need to be healed as soon as possible to avoid related complications. Anti-osteoporotic drugs targeting Wnt/β-catenin and PTH (parathyroid hormone) to promote fracture healing have become an important direction in recent years. Objective: Observe whether there is a difference in adult and aged situations by activating two signal paths. Methods: A single cortical hole with a diameter of 0.6 mm was made in the femoral metaphysis of Catnblox(ex3) mice and wild-type mice. The fracture healing effects of CA(Wnt/β-catenin activation) and PTH (activated by PTH (1–34) injections) were assessed by X-ray and CT imaging on days 7, 14, and 21 after fracture. The mRNA levels of β-catenin, PTH1R(Parathyroid hormone 1 receptor), and RUNX2(Runt-related transcription factor 2) in the fracture defect area were detected using RT-PCR. Angiogenesis and osteoblasts were observed by immunohistochemistry and osteoclasts were observed by TRAP (Tartrate-resistant Acid Phosphatase). Result: Adult CA mice and adult PTH mice showed slightly better fracture healing than adult wild-type (WT) mice, but there was no statistical difference. Aged CA mice showed better promotion of angiogenesis and osteoblasts and better fracture healing than aged PTH mice. Conclusion: The application of Wnt/β-catenin signaling pathway drugs for fracture healing in elderly patients may bring better early effects than PTH signaling pathway drugs, but the long-term effects need to be observed.