Effects of doxorubicin administration on bone strength and quality in sedentary and physically active Wistar rats

Summary

Doxorubicin (DOX) is used in pediatric cancer treatment. This study assessed the effects of 7 weeks of DOX and 10-week recovery on bone quality and biomechanical properties in sedentary and exercised Wistar rats. DOX decreases femur diaphysis radial growth and biomechanical properties. Some of these DOX effects were aggravated by exercise.

Introduction

Bone growth in pre-pubertal years critically influences adult fracture risk. DOX is widely used in the treatment of pediatric cancers, but there is limited evidence on its potential negative effects on bone growth. Exercise improves bone growth in children, but there is no evidence if it protects against DOX-induced bone toxicity. This study investigates the early and intermediate effects of a 7-week course of DOX on bone histomorphometry and strength in sedentary and exercised growing animal models.

Methods

Sixty-eight male Wistar rats (8 weeks) were treated with DOX (2 mg kg^?1) or vehicle for 7 weeks and afterward housed in standard cages or in cages with a running wheel and killed 2 or 10 weeks after last DOX administration. Femurs and blood were collected for assaying geometry, trabecular microarchitecture (histology), biomechanical properties (three-point bending and shearing of the femoral neck), bone calcium content and density (atomic absorption spectroscopy), and bone turnover markers (ELISA).

Results

DOX treatment reduced the femur diaphysis radial growth, with DOX-treated animals having a lower tissue area, cortical area, cortical thickness, and moment of inertia. DOX also decreased distal femur trabecular bone volume and trabecular number and increased trabecular separation. Femur diaphysis stiffness and maximum load were also reduced in past DOX-treated animals. Exercise was shown to worsen the effects of past DOX treatment on the femur diaphysis mechanical properties.

Conclusion

DOX negatively affects bone geometry, trabecular microarchitecture, and femur mechanical properties in growing Wistar rats. Exercise further aggravates the detrimental effects of past DOX treatment on bone mechanical properties.

     

Stiffness and strength of bone in osteoporotic patients treated with varying durations of oral bisphosphonates

Summary

Apparent modulus and failure stress of trabecular bone structure from 45 women with osteoporosis treated with bisphosphonates for varying durations were studied using finite element analyses and statistical modeling. Following adjustments for patient age and bone volume, increasing bisphosphonate treatment duration for up to 7.3 years was associated with treatment–time-dependent increases in bone apparent modulus and failure stress. Treatment durations exceeding 7.3 years were associated with time-dependent decreases in apparent modulus and failure stress from the peak values observed.

Introduction

The purpose of this study was to clarify the relationship between bisphosphonate (BP) treatment duration and human bone quality. This study quantified changes in the apparent modulus and failure stress of trabecular bone biopsied from patients with osteoporosis who were treated with BPs for widely varying durations.

Methods

Forty-five iliac crest bone samples were obtained from women with osteoporosis who were continuously treated with oral BPs for varying periods of up to 16 years. Micro-CT imaging was used to develop three-dimensional virtual models of the trabecular bone from these samples. Apparent modulus and failure stress of these virtual models were determined using finite element analyses (FEA). Polynomial regression and cubic splines, adjusted for relevant (age and BV/TV) covariates, were used to statistically model the data and quantify the relationships between BP treatment duration and apparent modulus or failure stress.

Results

Second-order polynomial models were needed to relate apparent modulus or failure stress to BP treatment duration. These models showed that these bone quality parameters (a) increased with increasing BP treatment duration up to approximately 7.3 years, (b) reached a maximum at this (~7.3 years) time, and then (c) declined with BP treatment durations exceeding ~7.3 years. A similar result was obtained by modeling with cubic splines.

Conclusions

Changes in FEA-derived apparent stiffness and failure stress are attributable to changes in trabecular bone structure, which in turn are related to the duration of BP treatment. These relationships are evident even after adjustments are made in the statistical models for changes in age and BV/TV. According to these models, increases in trabecular bone apparent stiffness and failure stress linked to BPs cease and appear to reverse after approximately 7.3 years of treatment. Conclusions regarding optimal BP therapy duration await study of additional bone quality parameters.

     

Our experience in the management of segmental bone defects caused by gunshots

Purpose

Bone and soft-tissue defects in the leg can be caused by high-energy trauma. One of the causes of extensive bone defects are gunshot injuries. The incidence of these has been noticeably increasing in recent years in countries with political instabilities due to the random availability of weapons. The aim of this study is to focus on the essentials of treatment of post-gunshot tibial bone loss using the Ilizarov concept.

Methods

In the period between June 2011 and July 2013, 30 patients with open tibial fractures after gunshots comprised the present study with an average follow-up of 18 months. The bone defect was associated with soft-tissue loss in 18 cases. All cases were subjected to extensive debridement of all devitalized tissues back to the healthy bone with viable soft tissue coverage. All cases were treated by the Ilizarov external fixator using the bifocal bone transport technique.

Results

The overall bone results were satisfactory in 28 cases (93.3 %). The overall functional results were satisfactory in 22 cases (73.3 %). The bone end results were significantly affected by age and smoking, while the functional end results were significantly affected by smoking, the presence of infection at the time of presentation, and complications during the procedure.

Conclusions

Bone transport is a reliable method in the treatment of gunshot bone defects of the tibia after extensive debridement of all the devitalized tissues. The Ilizarov external fixator allows the functional use of the limb throughout the course of treatment, preventing disuse osteoporosis and increasing patient satisfaction.

     

Irradiation Does Not Modify Mechanical Properties of Cancellous Bone Under Compression

Background

Gamma radiation sterilization can make cortical bone allograft more brittle, but whether it influences mechanical properties and propensity to form microscopic cracks in structurally intact cancellous bone allograft is unknown.

Questions/purposes

We therefore determined the effects of gamma radiation sterilization on structurally intact cancellous bone mechanical properties and damage formation in both low- and high-density femoral cancellous bone (volume fraction 9%–44%).

Methods

We studied 26 cancellous bone cores from the proximal and distal femurs of 10 human female cadavers (49–82 years of age) submitted to a single compressive load beyond yield. Mechanical properties and the formation of microscopic cracks and other tissue damage (identified through fluorochrome staining) were compared between irradiated and control specimens.

Results

We observed no alterations in mechanical properties with gamma radiation sterilization after taking into account variation in specimen porosity. No differences in microscopic tissue damage were observed between the groups.

Conclusions

Although gamma radiation sterilization influences the mechanical properties and failure processes in cortical bone, it does not appear to influence the performance of cancellous bone under uniaxial loading.

Clinical Relevance

Our observations support the use of radiation sterilization on structurally intact cancellous bone allograft.

     

Komplikationsmanagement im Internet Marketing

Background

New patients come more and more often over the internet; therefore internet marketing plays an increasingly important role.

Question

How can physicians build an effective internet marketing strategy and avoid complications?

Method

Selection and authorization of a reputable agency.

Results

New customer acquisition through high visibility in the internet, at the same time increasing the image and awareness.

Conclusions

In the overall “marketing mix” internet marketing has become indispensable to physicians who want to be successful. Those who are well positioned in Google are well known by their target audience and thus receive a higher response.

     

Prevalence of vitamin D insufficiency among adolescents and its correlation with bone parameters using high-resolution peripheral quantitative computed tomography

Summary

Vitamin D deficiency and insufficiency are highly prevalent among adolescents in Hong Kong, which is a sub-tropical city with ample sunshine. Vitamin D level is significantly correlated with key bone density and bone quality parameters. Further interventional studies are warranted to define the role of vitamin D supplementation for improvement of bone health among adolescents.

Introduction

The relationship between bone quality parameters and vitamin D (Vit-D) status remains undefined among adolescents. The aims of this study were to evaluate Vit-D status and its association with both bone density and bone quality parameters among adolescents.

Methods

Three hundred thirty-three girls and 230 boys (12–16 years old) with normal health were recruited in summer and winter separately from local schools. Serum 25(OH) Vit-D level, bone density and quality parameters by Dual Energy X-ray Absorptiometry (DXA) and High-Resolution peripheral Quantitative Computed Tomography (HR-pQCT), dietary calcium intake, and physical activity level were assessed.

Results

Sixty-four point seven percent and 11.4 % of subjects were insufficient [25?≤?25(OH)Vit-D?≤?50 nmol/L] and deficient [25(OH)Vit-D?<?25 nmol/L] in Vit-D, respectively. The mean level of serum 25(OH)Vit-D in summer was significantly higher than that in winter (44.7?±?13.6 and 35.9?±?12.6 nmol/L, respectively) without obvious gender difference. In girls, areal bone mineral density (aBMD) and bone mineral content (BMC) of bilateral femoral necks, cortical area, cortical thickness, total volumetric bone mineral density (vBMD), and trabecular thickness were significantly correlated with 25(OH)Vit-D levels. In boys, aBMD of bilateral femoral necks, BMC of the dominant femoral neck, cortical area, cortical thickness, total vBMD, trabecular vBMD, BV/TV, and trabecular separation were significantly correlated with 25(OH)Vit-D levels.

Conclusion

Vit-D insufficiency was highly prevalent among adolescents in Hong Kong with significant correlation between Vit-D levels and key bone density and bone quality parameters being detected in this study. Given that this is a cross-sectional study and causality relationship cannot be inferred, further interventional studies investigating the role of Vit-D supplementation on improving bone health among adolescents are warranted.

     

Die Arthrodese des Subtalargelenks

Objective

Realignment and stabilization of the hindfoot by subtalar joint arthrodesis.

Indications

Idiopathic/posttraumatic arthritis, inflammatory arthritis of the subtalar joint with/without hindfoot malalignment. Optional flatfoot/cavovarus foot reconstruction.

Contraindications

Inflammation, vascular disturbances, nicotine abuse.

Surgical technique

Approach dependent on assessment. Lateral approach: Supine position. Incision above the sinus tarsi. Exposure of subtalar joint. Removal of cartilage and breakage of the subchondral sclerosis. In valgus malalignment, interposition of corticocancellous bone segment; in varus malalignment resection of bone segment from the calcaneus. Reposition and temporarily stabilization with Kirschner wires. Imaging of hindfoot alignment. Stabilization with cannulated screws. Posterolateral approach: Prone position. Incision parallel to the lateral Achilles tendon border. Removal of cartilage and breakage of subchondral sclerosis. Medial approach: Supine position. Incision just above and parallel to the posterior tibial tendon. Removal of cartilage and breakage of subchondral sclerosis. Stabilization with screws.

Postoperative management

Lower leg walker with partial weightbearing. Active exercises of the ankle. After a 6?week X?ray, increase of weightbearing. Full weightbearing not before 8 weeks; with interpositioning bone grafts not before 10–12 weeks. Stable walking shoes. Active mobilization of the ankle.

Results

Of 43 isolated subtalar arthrodesis procedures, 5 wound healing disorders and no infections developed. Significantly improved AOFAS hindfood score. Well-aligned heel observed in 34 patients; 5 varus and 2 valgus malalignments. Sensory disturbances in 8 patients; minor ankle flexion limitations. Full bone healing in 36 subtalar joints, pseudarthrosis in 4 patients.

     

Harnröhrenrekonstruktion bei vorausgegangener Hypospadieoperation

Background

The tasks involved in reconstructing the urethra after failed hypospadias repair range from correction of a trivial meatal stenosis to reconstruction of the entire anterior urethra.

Objectives

To describe pathological findings in the urethra after failed hypospadias repair and the respective surgical methods used for their correction.

Materials and methods

The various pathological findings after unsuccessful hypospadias surgery are classified according to their location and complexity.

Results

The general rules of reconstruction that should be applied in each particular situation are described.

Conclusions

Successful reconstruction of the urethra in patients with failed hypospadias surgery requires experience and good knowledge of the anatomy of the normal and hypospadic urethra and penis. Mastery of plastic surgical techniques and profound knowledge of the various surgical methods of hypospadias surgery are essential.

     

Responsiveness and minimum important change of the Oswestry Disability Index in Italian subjects with symptomatic lumbar spondylolisthesis

Background

This study aims to investigate the responsiveness and the minimum important change of the Italian version of the Oswestry Disability Index (ODI-I) in subjects with symptomatic specific low back pain associated with lumbar spondylolisthesis (SPL).

Materials and methods

One hundred and fifty-one patients with symptomatic SPL completed the ODI-I, a 0–100 numerical rating scale (NRS), and performed the prone and supine bridge tests. The global perception of effectiveness was measured with a 7-point Likert scale. Responsiveness was assessed by distribution methods (minimum detectable change [MDC], effect size [ES], standardized response mean [SRM]) and anchor-based methods (ROC curves).

Results

The MDC was 4.23, the ES was 0.95 and the SRM was 1.25. ROC analysis revealed an area under the curve of 0.76 indicating moderate discriminating capacity. The best cut-off point for the dichotomous outcome was 7.5 (sensitivity 90.3%, specificity 56.7%). .

Conclusions

The ODI-I proved to be responsive in detecting changes after conservative treatment in subjects with lumbar SPL.

Level of evidence

II.

     

A brief history of FRAX

Summary

This paper reviews the research programme that went into the development of FRAX® and its impact in the 10 years since its release in 2008.

Introduction

Osteoporosis is defined on the measurement of bone mineral density though the clinical consequence is fracture. The sensitivity of bone mineral density measurements for fracture prediction is low, leading to the development of FRAX to better calculate the likelihood of fracture and target anti-osteoporosis treatments.

Methods

The method used in this paper is literature review.

Results

FRAX, developed over an 8-year period, was launched in 2008. Since the launch of FRAX, models have been made available for 64 countries and in 31 languages covering more than 80% of the world population.

Conclusion

FRAX provides an advance in fracture risk assessment and a reference technology platform for future improvements in performance characteristics.

     

Unicortical self-drilling external fixator pins reduce thermal effects during pin insertion

Introduction

External fixation is associated with the risk of pin loosening and pin infection potentially associated to thermal bone necrosis during pin insertion.

Objective

This study aims to investigate if the use of external fixator systems with unicortical pins reduces the heat production during pin insertion compared to fixators with bicortical pins.

Methods

Porcine bone specimens were employed to determine bone temperatures during insertion of fixator pins. Two thermographic cameras were used for a simultaneous temperature measurement on the bone surface (top view) and a bone cross-section (front view). Self-drilling unicortical and bicortical pins were inserted at different rotational speeds: (30–600) rpm. Maximum and mean temperatures of the emerging bone debris, bone surface and bone cross-section were analyzed.

Results

Maximum temperatures of up to 77?±?26 °C were measured during pin insertion in the emerging debris and up to 42?±?2 °C on the bone surface. Temperatures of the emerging debris increased with increasing rotational speeds. Bicortical pin insertion generated significantly higher temperatures at low insertion speed (30 rpm)

Conclusion

The insertion of external fixator pins can generate a considerable amount of heat around the pins, primarily emerging from bone debris and at higher insertion speeds. Our findings suggest that unicortical, self-drilling fixator pins have a decreased risk for thermal damage, both to the surrounding tissue and to the bone itself.

     

Impaired skeletal health and neuromuscular function among amphetamine users in clinical treatment

Summary

This study examined musculoskeletal health in amphetamine users, compared with healthy age-matched controls. We show that amphetamine users have reduced bone mass at several skeletal sites and attenuated maximal muscle strength and force development capacity in the lower extremities.

Introduction

Amphetamine use may cause poor bone quality and elevated risk of osteoporosis. The purpose of this study was to investigate whether amphetamine users exhibit reduced regional and whole body bone mineral density (BMD), altered bone metabolism, and how muscle function may relate to the patient groups’ skeletal health.

Methods

We assessed hip, lumbar spine and whole body BMD, and trabecular bone score (TBS) by dual x-ray absorptiometry (DXA), and bone metabolism markers in serum and maximal strength and force development capacity in 36 amphetamine users (25 men, 30?±?7 years; 11 women 35?±?10 years) and in 37 healthy controls (23 men, 31?±?9 years; 14 women, 35?±?7 years).

Results

Whole body BMD was lower in amphetamine users (8 % in males and 7 % females, p?<?0.01), as were BMD at the total hip and sub-regions of the hip (9–11 % in men and 10–11 % in women, p?<?0.05). Male users had 4 % lower TBS (p?<?0.05) and higher serum level of type 1 collagen amino-terminal propeptide (p?<?0.01). This coincided with reduced lower extremity maximal strength of 30 % (males, p?<?0.001) and 25 % (females, p?<?0.05) and 27 % slower muscular force development in males compared to controls (p?<?0.01).

Conclusions

These findings demonstrate that amphetamine users suffer from a generalized reduction in bone mass, which was associated with attenuated maximal muscle strength and force development capacity in the lower extremities.

     

Association of bone turnover markers with volumetric bone loss,periosteal apposition,and fracture risk in older men and women: the AGES-Reykjavik longitudinal study

Summary

Association between serum bone formation and resorption markers and cortical and trabecular bone loss and the concurrent periosteal apposition in a population-based cohort of 1069 older adults was assessed. BTM levels moderately reflect the cellular events at the endosteal and periosteal surfaces but are not associated with fracture risk.

Introduction

We assessed whether circulating bone formation and resorption markers (BTM) were individual predictors for trabecular and cortical bone loss, periosteal expansion, and fracture risk in older adults aged 66 to 93 years from the AGES-Reykjavik study.

Methods

The sample for the quantitative computed tomography (QCT)-derived cortical and trabecular BMD and periosteal expansion analysis consisted of 1069 participants (474 men and 595 women) who had complete baseline (2002 to 2006) and follow-up (2007 to 2011) hip QCT scans and serum baseline BTM. During the median follow-up of 11.7 years (range 5.4–12.5), 54 (11.4 %) men and 182 (30.6 %) women sustained at least one fracture of any type.

Results

Increase in BTM levels was associated with faster cortical and trabecular bone loss at the femoral neck and proximal femur in men and women. Higher BTM levels were positively related with periosteal expansion rate at the femoral neck in men. Markers were not associated with fracture risk.

Conclusion

This data corroborates the notion from few previous studies that both envelopes are metabolically active and that BTM levels may moderately reflect the cellular events at the endosteal and periosteal surfaces. However, our results do not support the routine use of BTM to assess fracture risk in older men and women. In light of these findings, further studies are justified to examine whether systemic markers of bone turnover might prove useful in monitoring skeletal remodeling events and the effects of current osteoporosis drugs at the periosteum.

     

Operative Behandlung der ulnaren Seitenbandläsion am Daumengrundgelenk

Objective

Reconstruction of the ruptured ulnar collateral ligament of the metacarpophalangeal (MP) joint of the thumb.

Indications

Ruptured ulnar collateral ligament of the thumb MP joint with instability: joint opening of more than 30° in flexion and more than 20° in extension, Stener lesion, displaced avulsion fractures.

Contraindications

Abrasions, wound-healing disturbance, skin disease, osteoarthritis.

Surgical technique

Curved skin incision dorsoulnar above the thumb MP joint. Protection of the branches of the superficial radial nerve. Incision of the adductor aponeurosis. Exposing the ulnar collateral ligament; opening and examination of the joint. Depending on the injury, primary suture repair, transosseous suture, repair with a bone anchor, osteosynthesis with K-wires or small screws in avulsion fracture, ligament reconstruction in chronic instability or older injury.

Postoperative treatment

Cast splint of the MP joint until swelling subsides; cast immobilization for 6 weeks; range-of-motion exercises, avoiding forced radial deviation of the MP joint for 3 months.

Results

Complete joint stability 3 months postoperatively in all 34 patients with rupture of the ulnar collateral ligament.

     

Allograft augmentation in proximal humerus fractures

Objective

Achieve stable fixation to initially start full range of motion (ROM) and to prevent secondary displacement in unstable fracture patterns and/or weak and osteoporotic bone.

Indications

(Secondarily) displaced proximal humerus fractures (PHF) with an unstable medial hinge and substantial bony deficiency, weak/osteoporotic bone, pre-existing psychiatric illnesses or patient incompliance to obey instructions.

Contraindications

Open/contaminated fractures, systemic immunodeficiency, prior graft-versus-host reaction.

Surgical technique

Deltopectoral approach. Identification of the rotator cuff. Disimpaction and reduction of the fracture, preparation of the situs. Graft preparation. Allografting. Fracture closure. Plate attachment. Definitive plate fixation. Radiological documentation. Postoperative shoulder fixation (sling).

Postoperative management

Cryotherapy, anti-inflammatory medication on demand. Shoulder sling for comfort. Full active physical therapy as tolerated without pain. Postoperative radiographs (anteroposterior, outlet, and axial [as tolerated] views) and clinical follow-up after 6 weeks and 3, 6, and 12 months.

Results

Bony union and allograft incorporation in 9 of 10 noncompliant, high-risk patients (median age 63 years) after a mean follow-up of 28.5 months. The median Constant–Murley Score was 72.0 (range 45–86). Compared to the uninjured contralateral side, flexion was impaired by 13?%, abduction by 14?%, and external rotation by 15?%. Mean correction of the initial varus displacement was 38° (51° preoperatively to 13° postoperatively).

     

Inflammation and the bone-vascular axis in end-stage renal disease

Summary

Bone loss and vascular calcification coincide in patients with end-stage renal disease, similar as to what is observed in the general population. In the present bone biopsy study, we provide further evidence that (micro-)inflammation may represent a common soil for both diseases.

Introduction

Vascular calcification is a common complication of end-stage renal disease (ESRD) and is predictive of subsequent cardiovascular disease and mortality. Mounting evidence linking bone disorders with vascular calcification has contributed to the development of the concept of the bone-vascular axis. Inflammation is involved in the pathogenesis of both disorders. The aim of the present study was to evaluate the relationship between aortic calcification, inflammation, and bone histomorphometry in patients with ESRD.

Methods

Parameters of inflammation and mineral metabolism were assessed in 81 ESRD patients (55?±?13 year, 68 % male) referred for renal transplantation. Static bone histomorphometry parameters were determined on transiliac bone biopsies performed during the transplant procedure. Aortic calcification was quantified on lateral lumbar X-rays using the Kauppila method.

Results

Aortic calcification, low bone turnover, and low bone area were observed in 53, 37, and 21 % of patients respectively. Inflammatory markers were found to be independently associated with aortic calcification (hsIL-6) and low bone area (TNF-α). Low bone area associated with aortic calcification, independent of age, diabetes, and inflammation.

Conclusions

Low bone area and inflammation associates with aortic calcification, independent of each other and traditional risk factors. Our data emphasize the role of (micro-)inflammation in the bone-vascular axis in CKD.

     

Bone status in glucocorticoid-treated men and women

Summary

We recorded the results of areal bone mineral density (aBMD) and microarchitecture of the bone measured by trabecular bone score (TBS) in 416 glucocorticoid-treated men and women aged 40 years and older with or without fracture to 1104 controls. TBS better discriminated those with fracture compared to aBMD. These differences were the greatest in men.

Introduction

The aim of this study is to evaluate glucocorticoid (GC)-induced effects on areal bone mineral density (aBMD) and bone microarchitectural texture measured by trabecular bone score (TBS).

Methods

TBS and aBMD were evaluated at L1–L4 postero-anterior (PA) spine by dual X-ray absorptiometry (DXA) in 1520 men and women aged 40 years and over. Four hundred sixteen subjects who received GCs (≥5 mg/day, for ≥3 months) were matched with 1104 sex-, age-, and BMI-matched control subjects. Clinical data, osteoporotic fractures (OPF), and dietary habits were documented in the medical report.

Results

GC-treated patients were characterized by a significant decrease of TBS (1.267 vs. 1.298, p?<?0.001) compared with control-matched subjects while no change in BMD was observed at any sites. These decreases were even more pronounced when fracture status was taken into account (1.222 vs. 1.298, p?<?0.001). The odds ratio (OR) for TBS was 1.44 (1.095–1.89) for OPF, whereas no association was found for BMD at any sites (all p?>?0.3). A similar effect on microarchitecture measured by TBS was seen by the presence of fracture as by the use of glucocorticoids. An influence on TBS by sex was also noted with a decrease in TBS of greater magnitude in men.

Conclusions

GC-treated individuals have a significant deterioration of bone microarchitectural texture as assessed by TBS which is more marked in those with OPF and in men. TBS seems to be more sensitive than aBMD for GC-related fracture detection and should be a good surrogate indicator of bone health in such secondary osteoporosis.

     

Teriparatide improves volumetric bone mineral density and fine bone structure in the UIV+1 vertebra,and reduces bone failure type PJK after surgery for adult spinal deformity

Summary

We conducted a prospective comparative study of the effect of teriparatide therapy for preventing vertebral-failure-type PJK after reconstructive surgery for adult spinal deformity. Prophylactic teriparatide improved the volumetric bone mineral density and fine bone structure of the vertebra above the upper-instrumented vertebra and reduced the incidence of vertebral-failure-type PJK.

Introduction

Proximal junctional kyphosis (PJK) is a complication after corrective surgery for spinal deformity. This study sought to determine whether teriparatide (TP) is an effective prophylactic against PJK type 2 (vertebral fracture) in surgically treated patients with adult spinal deformity (ASD).

Methods

Forty-three patients who started TP therapy immediately after surgery and 33 patients who did not receive TP were enrolled in this prospective case series. These patients were female, over 50, surgically treated for ASD, and followed for at least 2 years. Preoperative and postoperative standing whole-spine X-rays and dual-energy X-ray absorptiometry scans, and multidetector CT images obtained before and 6 months after surgery were used to analyze the bone strength in the vertebra above the upper-instrumented vertebra (UIV+1).

Results

Mean age was 67.9 years. After 6 months of treatment, mean hip-bone mineral density (BMD) increased from 0.721 to 0.771 g/cm² in the TP group and decreased from 0.759 to 0.729 g/cm² in the control group. This percent BMD change between groups was significant (p?<?0.05). The volumetric BMD (326 to 366 mg/cm³) and bone mineral content (BMC) (553 to 622 mg) at UIV+1 were also significantly increased in TP group. The bone volume/tissue volume ratio increased from 46 to 54 % in the TP group, and the trabecular bone thickness and number increased by 14 and 5 %, respectively. At the 2-year follow-up, the PJK type 2 incidence was significantly lower in the TP group (4.6 %) than in the control group (15.2 %; p?=?.02).

Conclusions

Prophylactic TP treatment improved the volumetric BMD and fine bone structure at UIV+1 and reduced the PJK-type 2 incidence.