Osteoid osteoma in the ankle and foot. An overview of 50 years of experience.

BACKGROUND: The literature published about osteoid osteoma (OO) in the ankle-foot consists mainly on case reports. METHODS: We performed a retrospective study in which we analyzed demographic parameters, pain characteristics, treatment options and functional outcomes measured using the AOFAS and the SEFAS scales. RESULTS: We treated 17 patients with OO around the ankle-foot. Eighty-eight percent of patients had night pain that was relieved with NSAIDs. The bones most often affected were the talus and calcaneus. OO was diagnosed 21 months after the onset of symptoms. Mean follow-up was 17.3 years. The surgical techniques most used were curettage and curettage and bone grafting. There was a significant increase in AOFAS and SEFAS scores after surgery. CONCLUSIONS: Suspicion is the base of a prompt and a correct diagnosis of OO. The OO should be especially suspected in patients who present night pain that can be relieved with NSAIDs.

The efficacy of an intramedullary nitinol implant in the correction of claw toe or hammertoe deformities.

INTRODUCTION: A multitude of procedures has been described in the literature for the treatment of lesser toe deformities and there is currently no general consensus on the optimal method of fixation. The aim of this study is to assess the clinical and radiological outcomes of an intramedullary nitinol implant for the correction of lesser toe deformities, and to determine if the distal interphalangeal (DIP) joint and metatarsophalangeal (MTP) joint are modified during patient follow-up after correction of the PIP joint. MATERIALS AND METHODS: A prospective analysis of 36 patients with claw toe or hammertoe who were treated with an intramedullary nitinol implant. Clinical manifestations and angulation of the metatarsophalangeal, proximal and distal interphalangeal (MTP, PIP, DIP) joints were evaluated in radiographic studies preoperatively, at first medical revision post-surgery, and after a minimum of 1 year of follow-up. Complications such as non-union rate, implant rupture, and implant infection were also evaluated during follow-up. RESULTS: All patients were women with an average age of 65.5 (range 47-82) years. The average follow-up time was 2.4 (range 1-5.7) years. Fifty intramedullary nitinol implants were used. The MTP joint extension and PIP joint flexion decreased by 15.9° (95% CI - 19.11 to - 12.63) and 49.4° (95% CI - 55.29 to - 43.52), respectively, at the end of follow-up. Moreover, the DIP joint flexion increased progressively during follow-up (13.7° pre-surgery versus 35.6 in last medical check-up, 95% CI 13.24-30.57). There were four (8%) asymptomatic implant ruptures. The rate of fusion was 98%. CONCLUSION: The reduction of the PIP joint using an intramedullary nitinol implant is a good option in lesser toe deformities, with few complications and a high rate of arthrodesis. Moreover, the PIP joint reduction affects both the MTP and DIP joints.

Local and systemic diffusion of antineoplastic drugs following vertebroplasty using acrylic cement mixed with cisplatin or methotrexate: experimental study in pigs.

PURPOSE: To determine the efficacy of cisplatin- or methotrexate-containing acrylic cement for local and systemic antineoplastic drug diffusion. Among the uses of acrylic cement or Polymethylmethacrylate (PMMA), there is the possibility to employ it as vehicle for drug diffusion. This capability is of interest in the treatment of pathological fractures: The curative effects of the cement (cytotoxicity of the monomer and increased temperature) are added to the antineoplastic effect of the drugs. METHODS: In the experimental study, two groups of ten pigs underwent vertebroplasty using cement mixed with 500 mg of powder cisplatin or 1000 mg of powder methotrexate. Vertebroplasty was performed in two non-consecutive lumbar vertebrae with bipedicular cement injection. Transpedicular bone biopsy was performed weekly to measure levels of antineoplastic agent in bone tissue and blood plasma. Cisplatin was studied by atomic absorption spectrometry and methotrexate by fluorescence polarization immunoassay. Renal and hepatic function and blood analysis were performed weekly. RESULTS: Cisplatin and methotrexate levels were found in bone tissue at more than 5 weeks following surgery. The cisplatin peak occurred at week 3 (mean 1269 µg/g bone) and the methotrexate peak at week 1 (mean 862.76 µg/g bone). Plasma drug levels were found 72 h after surgery, with a peak at 24 h for cisplatin (mean 0.23 µmol/L) and at 30 min for methotrexate (mean 0.92 µmol/L). None of the animals died during the study. Animals with intracanal cement leaks showed no neurological involvement. Renal, hepatic and hemogram studies remained within normal limits. CONCLUSIONS: There is local diffusion of antineoplastic agents from the cement to bone and plasma. We found methotrexate and cisplatin levels in bone at up to 5 weeks, comparable to previous in vitro reports. At the doses administered, there were no cases of myelosuppression, hepatotoxicity, or nephrotoxicity.

Reconstruction of the extensor mechanism with fresh-frozen tendon allograft in total knee arthroplasty.

PURPOSE: Patellar tendon rupture after total knee replacement is a rare and highly limiting injury with multifactorial aetiology. Many reconstruction techniques have been described with not very predictable results. The use of allografts has been accepted as a suitable solution. METHODS: A series of seven patients with patellar tendon rupture treated with fresh-frozen tendon allograft reconstruction after knee arthroplasty is presented. RESULTS: Median follow-up is 25 months (20-31). Functional assessment improved, and the knee society score and knee functional score improved from 26 and 16 to 82 and 55, respectively. Median extension lag was 5° (0°-20°), with a median range of motion of 95° (70-100). Radiological study showed a rise of the patella of 22.26 mm. CONCLUSION: The use of fresh-frozen allografts as a solution to patellar tendon ruptures after knee arthroplasty seems to provide acceptable results. Increased patellar height does not seem to affect functionality. LEVEL OF EVIDENCE: Case series, Level IV.

HDACi vorinostat protects muscle from degeneration after acute rotator cuff injury in mice.

Aims: Rotator cuff (RC) injuries are characterized by tendon rupture, muscle atrophy, retraction, and fatty infiltration, which increase injury severity and jeopardize adequate tendon repair. Epigenetic drugs, such as histone deacetylase inhibitors (HDACis), possess the capacity to redefine the molecular signature of cells, and they may have the potential to inhibit the transformation of the fibro-adipogenic progenitors (FAPs) within the skeletal muscle into adipocyte-like cells, concurrently enhancing the myogenic potential of the satellite cells. Methods: HDACis were added to FAPs and satellite cell cultures isolated from mice. The HDACi vorinostat was additionally administered into a RC injury animal model. Histological analysis was carried out on the isolated supra- and infraspinatus muscles to assess vorinostat anti-muscle degeneration potential. Results: Vorinostat, a HDACi compound, blocked the adipogenic transformation of muscle-associated FAPs in culture, promoting myogenic progression of the satellite cells. Furthermore, it protected muscle from degeneration after acute RC in mice in the earlier muscle degenerative stage after tenotomy. Conclusion: The HDACi vorinostat may be a candidate to prevent early muscular degeneration after RC injury.

The effects of a prehabilitation programme based on therapeutic exercise, back care education, and pain neuroscience education in patients scheduled for lumbar radiculopathy surgery: A study protocol for a randomised controlled trial.

The aim of this present clinical trial is to evaluate the effectiveness of a multicomponent prehabilitation programme administered through educational videos versus another programme based on written exercise recommendations, in patients scheduled for lumbar radiculopathy surgery. This study will be a multicentre, controlled, randomised, parallel clinical trial. One hundred participants undergoing lumbar radiculopathy surgery who meet the established inclusion criteria will be recruited at different Spanish hospitals. The experimental group will follow a 4-week prehabilitation programme combining therapeutic exercise, back care education, and pain neuroscience education delivered through videos designed for consumption at home. The control group will be provided with written instructions to perform therapeutic exercises during the same prehabilitation time period. The primary outcome of the study will be disability, assessed using the Spanish version of the Oswestry Disability Index. The secondary outcomes will be pain perception, health-related quality of life, fear avoidance, kinesiophobia, catastrophising, anxiety, depression, physical activity, and the treatment satisfaction of the patients. This study will provide evidence for the effectiveness of a home-based multicomponent prehabilitation programme that addresses some already identified barriers to patient attendance in face-to-face programmes. Understanding the medium and long-term effects of pre-surgery lumbar muscle training and pain neuroscience education administered via instructional videos watched by patients at home, will help improve the design of prehabilitation programmes in this population while also improving the cost-effectiveness of such interventions.

Clinical Outcome and Histological Findings After Induced Leakage of PMMA Loaded With Methotrexate and Cisplatin During Vertebroplasty: Experimental Model in Pigs.

STUDY DESIGN: Animal experimental model. OBJECTIVE: To study the clinical behavior and histological changes in the spinal cord, nerve roots and perivertebral muscles of the spine after induced leakage of polymethylmethacrylate (PMMA) loaded with antiblastic drugs during vertebroplasty in an animal model of pigs. METHODS: We performed vertebroplasty on 25 pigs. The animals were divided into 3 groups: vertebroplasty with PMMA alone (control group), vertebroplasty with PMMA loaded with methotrexate (MTX) and vertebroplasty with PMMA loaded with cisplatin (CYS). At 2 vertebral levels, epidural and prevertebral, massive cement leaks were induced. Animals were evaluated daily. Two weeks later, the pigs were sacrificed, and the tissues that came in contact with the cement were analyzed. RESULTS: The clinical results for each of the groups were reported. The control group had no clinical alterations. In the MTX group, 2 pigs died before 1 week due to pneumonitis. In the CYS group, 4 animals had motor impairment, and 3 of the 4 had paraplegia. The histological results were as follows: the control and MTX groups showed synovial metaplasia, inflammatory reaction, crystal deposits, and giant cell reaction in the dura mater and muscle and all the animals in the CYS group had spinal cord and muscular necrosis. CONCLUSIONS: Massive cement leak after vertebroplasty with PMMA loaded with cisplatin is extremely toxic to the spinal cord and muscles around the spine. Therefore, its use cannot be recommended for the treatment of vertebral metastases. Using PMMA loaded with methotrexate seems to be a safe procedure, but further research is needed.

Vertebral Body Height Changes in Acute Symptomatic Osteoporotic Vertebral Compression Fractures Treated with Vertebral Cement Augmentation-Which Factors Affect Vertebral Body Height during Follow-up? A Multiple Linear Regression Study.

Changes in vertebral body height depend on various factors which were analyzed in isolation and not as a whole. The aim of this study is to analyze what factors might influence the restoration of the vertebral body height after vertebral augmentation. We analyzed 48 patients (108 vertebrae) with osteoporotic vertebral fractures who underwent vertebral augmentation when a conservative treatment proved to be unsatisfactory. The analyses were carried out at the time of the fracture, during surgery (pre-cementation and post-cementation), at the first medical check-up (6 weeks post-surgery) and at the last medical check-up. The average vertebral height was measured, and the differences from the preoperative values were calculated at each timepoint. A Pearson correlation coefficient and a linear multivariable regression were carried out at different timepoints. The time since the vertebral fracture was 60.4 ± 41.7 days. The patients' average age was 73.8 ± 7 years. The total follow-up period was 1.43 ± 1 year. After vertebral cementation, there was an increase in the vertebral body height of +0.3 cm (13.6%). During the post-operative follow-up, there was a progressive collapse of the vertebral body, and the pre-surgical height was reached. The factors that most influenced the vertebral height restoration were: a grade III collapse, an intervertebral-vacuum-cleft (IVVC) and the use of a flexible trocar before cement augmentation. The factor that negatively influenced the vertebral body height restoration was the location of the thoracolumbar spine.

Novel porcine experimental model of severe progressive thoracic scoliosis with compensatory curves induced by interpedicular bent rigid temporary tethering.

Using flexible tethering techniques, porcine models of experimental scoliosis have shown scoliotic curves with vertebral wedging but very limited axial rotation. The aim of this experimental work was to induce a severe progressive scoliosis in a growing porcine model for research purposes. A unilateral spinal bent rigid tether was anchored to two ipsilateral pedicle screws in eight pigs. The spinal tether was removed after 8 weeks. Ten weeks later, the animals were sacrificed. Conventional radiographs and 3D CT-scans were taken to evaluate changes in the alignment of the thoracic spine. After the first 8 weeks of rigid tethering, all animals developed scoliotic curves (mean Cobb angle: 24.3°). Once the interpedicular tether was removed, the scoliotic curves progressed in all animals during 10 weeks reaching a mean Cobb angle of 49.9°. The sagittal alignment of the thoracic spine showed loss of physiologic kyphosis (Mean: -18.3°). Axial rotation ranged from 10° to 49° (Mean 25.7°). Release of the spinal tether results in progression of the deformity with the development of proximal and distal compensatory curves. In conclusion, temporary interpedicular tethering at the thoracic spine induces severe scoliotic curves in pigs, with significant wedging and rotation of the vertebral bodies, and true compensatory curves. CLINICAL RELEVANCE: The tether release model will be used to evaluate corrective non-fusion technologies in future investigations. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:174-182, 2018.