Markus Loibl

Habitual Physical Activity and Sports Participation After Total Ankle Arthroplasty

Background There is a lack of detailed information about habitual physical activity levels and the sports participation of patients after total ankle arthroplasty. Hypothesis The proportion of sports active patients increases after total ankle arthroplasty, and the majority of patients will meet current recommendations for health-enhancing physical activity. Study Design Case series; Level of evidence, 4. Methods The authors assessed the pre- and postoperative participation in sports and recreational activities of 101 patients at a mean of 3.7 years after total ankle arthroplasty. Activity levels were determined with use of the University of California at Los Angeles (UCLA) activity scale. The International Physical Activity Questionnaire (IPAQ) was used to quantify habitual physical activity levels and to calculate the proportion of patients meeting current guidelines for health-enhancing physical activity. The American Orthopaedic Foot and Ankle Society (AOFAS) hindfoot score was used as the clinical outcome measure. Radiographs were studied for tibial and talar radiolucencies, and any association between radiolucencies, activity levels, and sports participation was determined. Results Preoperatively, 62.4% of the patients were active in sports; 66.3% were active after surgery (P = .56). The patients were active in 3.0 ± 1.8 different sports and recreational activities preoperatively and in 3.0 ± 1.6 activities after surgery (P = 1.0). The sports frequency remained unchanged, with 2.0 ± 1.6 sessions per week before total ankle arthroplasty and 2.3 ± 1.7 sessions per week postoperatively (P = .19). Overall, the patients were active in sports and recreation for 3.9 ± 3.8 hours per week preoperatively, and for 4.7 ± 3.9 hours per week after surgery (P = .14). The most common disciplines after total ankle arthroplasty were swimming, cycling, and fitness/weight training. Sixty-five percent of the patients stated that surgery had improved their sports ability. The UCLA activity levels increased significantly from 4.3 ± 2.2 to 6.2 ± 1.6 (P < .001); AOFAS scores also improved significantly from 45.5 ± 16.6 to 84.3 ± 13.3 (P < .001). Patients suffering from posttraumatic ankle osteoarthritis were less satisfied with surgery than those with primary or inflammatory ankle osteoarthritis. Seventy-nine percent of the patients met the current guidelines for health-enhancing physical activity according to the IPAQ. Neither sports participation nor activity levels were associated with the presence of periprosthetic radiolucencies. Conclusion Two-thirds of the patients were active in sports after total ankle arthroplasty, and the majority of the patients met current health-enhancing physical activity recommendations. The clinical outcome as determined by AOFAS scores and the patient satisfaction were favorable. The present study found no association between sports participation, increased physical activity levels, and the appearance of periprosthetic radiolucencies 3.7 years after total ankle arthroplasty. However, these results have to be confirmed after longer follow-up, in particular of those patients regularly participating in sports with higher impact.

Sports Activity After Surgical Treatment of Intra-articular Tibial Plateau Fractures in Skiers

Background: Tibial plateau fractures occur frequently while participating in winter sports, but there is no information on whether skiers can resume sports and recreational activities after internal fixation of these fractures. Hypothesis: Skiers can resume low-impact sports activity after internal fixation of tibial plateau fractures. Study Design: Case series; Level of evidence, 4. Methods: A total of 103 patients were surveyed by postal questionnaires to determine their sports activities at a mean of 7.8 ± 1.8 years after internal fixation of intra-articular tibial plateau fractures. The survey also included the Lysholm score, the Tegner activity scale, and a visual analog scale (VAS) for pain. Results: At the time of the survey, 88% of the patients were engaged in sports activities (rate of return to sports, 88%), and 53% continued to participate in downhill skiing. The median number of different activities declined from 5 (range, 1-17) preoperatively to 4 (range, 0-11) postoperatively (P < .01). Sports frequency and duration per week did not change: 3 (range, 1-7) preoperatively versus 3 (range, 0-7) postoperatively (P = .275) and 4 hours (range, 1-16 hours) preoperatively versus 3.5 hours (range, 0-15 hours) postoperatively (P = .217), respectively. Median values of all outcome scores declined: Lysholm score, 100 (range, 85-100) preoperatively versus 94.5 (range, 37-100) postoperatively (P < .01); VAS, 0 (range, 0-7) preoperatively versus 1 (range, 0-8) postoperatively (P < .01). Median Tegner activity scale scores declined in all age groups except for patients aged 51 to 60 years. The ability to participate in sports at the time of follow-up compared with the ability before the accident was rated as “similar” by 57 patients (62.0%) and as “worse” by 35 patients (38.0%). The more severe fracture types, B3 and C3 according to the AO classification system, were associated with poorer outcomes related to return to sports and functional scores. Conclusion: A large percentage of skiers with surgically treated intra-articular tibial plateau fractures cannot continue to participate in downhill skiing; however, the majority could resume an active lifestyle for several years after the trauma. Fracture type seems to be an important factor influencing physical activity and general functional outcome.

Are Applied Growth Factors Able to Mimic the Positive Effects of Mesenchymal Stem Cells on the Regeneration of Meniscus in the Avascular Zone

Meniscal lesions in the avascular zone are still a problem in traumatology. Tissue Engineering approaches with mesenchymal stem cells (MSCs) showed successful regeneration of meniscal defects in the avascular zone. However, in daily clinical practice, a single stage regenerative treatment would be preferable for meniscus injuries. In particular, clinically applicable bioactive substances or isolated growth factors like platelet-rich plasma (PRP) or bone morphogenic protein 7 (BMP7) are in the focus of interest. In this study, the effects of PRP and BMP7 on the regeneration of avascular meniscal defects were evaluated. In vitro analysis showed that PRP secretes multiple growth factors over a period of 8 days. BMP7 enhances the collagen II deposition in an aggregate culture model of MSCs. However applied to meniscal defects PRP or BMP7 in combination with a hyaluronan collagen composite matrix failed to significantly improve meniscus healing in the avascular zone in a rabbit model after 3 months. Further information of the repair mechanism at the defect site is needed to develop special release systems or carriers for the appropriate application of growth factors to support biological augmentation of meniscus regeneration.

Adipose Tissue-Derived Stem Cell Secreted IGF-1 Protects Myoblasts from the Negative Effect of Myostatin

Myostatin, a TGF-β family member, is associated with inhibition of muscle growth and differentiation and might interact with the IGF-1 signaling pathway. Since IGF-1 is secreted at a bioactive level by adipose tissue-derived mesenchymal stem cells (ASCs), these cells (ASCs) provide a therapeutic option for Duchenne Muscular Dystrophy (DMD). But the protective effect of stem cell secreted IGF-1 on myoblast under high level of myostatin remains unclear. In the present study murine myoblasts were exposed to myostatin under presence of ASCs conditioned medium and investigated for proliferation and apoptosis. The protective effect of IGF-1 was further examined by using IGF-1 neutralizing and receptor antibodies as well as gene silencing RNAi technology. MyoD expression was detected to identify impact of IGF-1 on myoblasts differentiation when exposed to myostatin. IGF-1 was accountable for 43.6% of the antiapoptotic impact and 48.8% for the proliferative effect of ASCs conditioned medium. Furthermore, IGF-1 restored mRNA and protein MyoD expression of myoblasts under risk. Beside fusion and transdifferentiation the beneficial effect of ASCs is mediated by paracrine secreted cytokines, particularly IGF-1. The present study underlines the potential of ASCs as a therapeutic option for Duchenne muscular dystrophy and other dystrophic muscle diseases.

The effect of leukocyte-reduced platelet-rich plasma on the proliferation of autologous adipose-tissue derived mesenchymal stem cells1

Clinical application of platelet-rich plasma (PRP) and stem cells has become more and more important in regenerative medicine during the last decade. However, differences in PRP preparations may contribute to variable PRP compositions with unpredictable effects on a cellular level. In the present study, we modified the centrifugation settings in order to provide a leukocyte-reduced PRP and evaluated the interactions between PRP and adipose-tissue derived mesenchymal stem cells (ASCs).PRP was obtained after modification of three different centrifugation settings and investigated by hemogram analysis, quantification of protein content and growth factor concentration. ASCs were cultured in serum-free α-MEM supplemented with autologous 10% or 20% leukocyte-reduced PRP. Cell cycle kinetics of ASCs were analyzed using flow cytometric analyses after 48 hours.Thrombocytes in PRP were concentrated, whereas erythrocytes, and white blood cells (WBC) were reduced, independent of centrifugation settings. Disabling the brake further reduced the number of WBCs. A higher percentage of cells in the S-phase in the presence of 20% PRP in comparison to 10% PRP and 20% fetal calf serum (FCS) advocates the proliferation stimulation of ASCs.These findings clearly demonstrate considerable differences between three PRP separation settings and assist in safeguarding the combination of leukocyte-reduced PRP and stem cells for regenerative therapies.

Endothelial Progenitor Cell Fraction Contained in Bone Marrow-Derived Mesenchymal Stem Cell Populations Impairs Osteogenic Differentiation.

In bone tissue engineering (TE) endothelial cell-osteoblast cocultures are known to induce synergies of cell differentiation and activity. Bone marrow mononucleated cells (BMCs) are a rich source of mesenchymal stem cells (MSCs) able to develop an osteogenic phenotype. Endothelial progenitor cells (EPCs) are also present within BMC. In this study we investigate the effect of EPCs present in the BMC population on MSCs osteogenic differentiation. Human BMCs were isolated and separated into two populations. The MSC population was selected through plastic adhesion capacity. EPCs (CD34+ and CD133+) were removed from the BMC population and the resulting population was named depleted MSCs. Both populations were cultured over 28 days in osteogenic medium (Dex+) or medium containing platelet lysate (PL). MSC population grew faster than depleted MSCs in both media, and PL containing medium accelerated the proliferation for both populations. Cell differentiation was much higher in Dex+ medium in both cases. Real-time RT-PCR revealed upregulation of osteogenic marker genes in depleted MSCs. Higher values of ALP activity and matrix mineralization analyses confirmed these results. Our study advocates that absence of EPCs in the MSC population enables higher osteogenic gene expression and matrix mineralization and therefore may lead to advanced bone neoformation necessary for TE constructs.

Biologic agents for anterior cruciate ligament healing: A systematic review

AIM To systematically review the currently available literature concerning the application of biologic agents such as platelet-rich plasma (PRP) and stem cells to promote anterior cruciate ligament (ACL) healing. METHODS A systematic review of the literature was performed on the use of biologic agents (i.e., PRP or stem cells) to favor ACL healing during reconstruction or repair. The following inclusion criteria for relevant articles were used: Clinical reports of any level of evidence, written in English language, on the use of PRP or stem cells during ACL reconstruction/repair. Exclusion criteria were articles written in other languages, reviews, or studies analyzing other applications of PRP/stem cells in knee surgery not related to promoting ACL healing. RESULTS The database search identified 394 records that were screened. A total of 23 studies were included in the final analysis: In one paper stem cells were applied for ACL healing, in one paper there was a concomitant application of PRP and stem cells, whereas in the remaining 21 papers PRP was used. Based on the ACL injury pattern, two papers investigated biologic agents in ACL partial tears whereas 21 papers in ACL reconstruction. Looking at the quality of the available literature, 17 out of 21 studies dealing with ACL reconstruction were randomized controlled trials. Both studies on ACL repair were case series. CONCLUSION There is a paucity of clinical trials investigating the role of stem cells in promoting ACL healing both in case of partial and complete tears. The role of PRP is still controversial and the only advantage emerging from the literature is related to a better graft maturation over time, without documenting beneficial effects in terms of clinical outcome, bone-graft integration and prevention of bony tunnel enlargement.

Leukocyte-Reduced Platelet-Rich Plasma Treatment of Basal Thumb Arthritis: A Pilot Study

A positive effect of intra-articular platelet-rich plasma (PRP) injection has been discussed for osteoarthritic joint conditions in the last years. The purpose of this study was to evaluate PRP injection into the trapeziometacarpal (TMC) joint. We report about ten patients with TMC joint osteoarthritis (OA) that were treated with 2 intra-articular PRP injections 4 weeks apart. PRP was produced using the Double Syringe System (Arthrex Inc., Naples, Florida, USA). A total volume of 1.47 ± 0.25 mL PRP was injected at the first injection and 1.5 ± 0.41 mL at the second injection, depending on the volume capacity of the joint. Patients were evaluated using VAS, strength measures, and the Mayo Wrist score and DASH score after 3 and 6 months. VAS significantly decreased from 6.2 ± 1.6 to 5.4 ± 2.2 at six-month follow-up (P < 0.05). The DASH score was unaffected; however, the Mayo Wrist score significantly improved from 46.5 ± 18.6 to 67.5 ± 19.0 at six-month follow-up (P = 0.05). Grip was unaffected, whereas pinch declined from 6.02 ± 2.99 to 3.96 ± 1.77 at six-month follow-up (P < 0.05). We did not observe adverse events after the injection of PRP, except one occurrence of a palmar wrist ganglion, which resolved without treatment. PRP injection for symptomatic TMC OA is a reasonable therapeutic option in early stages TMC OA and can be performed with little to no morbidity.

Spinal fracture reduction with a minimal-invasive transpedicular Schanz Screw system: clinical and radiological one-year follow-up.

INTRODUCTION Surgical management of thoracolumbar trauma involves correction of posttraumatic deformity and placement of transpedicular instrumentation. The aim of this prospective cohort study was to generate first results reflecting the clinical and radiological outcome of patients treated with percutaneous dorsal instrumentation for fractures of the thoracic and lumbar spine with the use of a transpedicular new Schanz Screw system (USS Fracture MIS, DePuy Synthes). METHODS A total of 26 patients with fractures of the thoracic and lumbar spine were operatively treated with bi-segmental dorsal instrumentation between January and December 2012. Radiological data acquisition was performed pre- and postoperatively, after six weeks, three, six, and twelve months. The radiological parameter of interest was the bi-segmental kyphotic end plate angle (Cobb angle). The Chronic Disability Index (CDI), the Oswestry Disability Index (ODI), and the Spine Tango Core Outcome Measurement Index (COMI) were applied to investigate the clinical outcome. RESULTS The clinical follow-up was completed by 22 patients (84.6%), and the radiological follow-up by 21 (80.8%) patients. Our patient population had a mean age of 47.4 ± 4.1 years. Twelve patients received dorsal instrumentation, and 14 patients were treated with an additional ventral reconstruction. Intraoperative reduction was 11.5 ± 1.5° among all patients (p < 0.01). A considerable amount of the operative correction was lost after six weeks with a loss of reduction of 4.6 ± 1.4° (p < 0.01). At one year follow-up, the measured loss of reduction was significant in comparison to the postoperative state, 6.9 ± 1.3° among all patients, 8.7 ± 2.1° after dorsal and 4.9 ± 1.1° after dorsoventral stabilisation (all p < 0.01). Moreover, all patients had minimal to moderate disability with a CDI of 1.8 ± 0.4 (0 - 7), and an ODI of 15.6 ± 3.6 (0 - 60). CONCLUSION The new transpedicular Schanz screw system can deliver a correction and stabilization of thoracic and lumbar spine fractures. Patients report minimal to moderate disability as a result of their severe injury one year after trauma. We advocate the use of the transpedicular Schanz screw system to correct posttraumatic kyphotic deformity, with secondary anterior fusion in our treatment strategy of thoracolumbar incomplete burst fractures in patients without a neurologic deficit.

Pediatric Cervical Spine Injuries: A Rare But Challenging Entity.

Background: Injuries to the cervical spine in pediatric patients are uncommon. A missed injury can have devastating consequences in this age group. Because of the lack of routine in diagnosis and management of pediatric cervical spine injuries (PCSI), each of these cases represents a logistic and personal challenge. Methods: By means of clinical cases, we demonstrate key points in diagnostics and treatment of pediatric spine injuries. We highlight typical pediatric injury patterns and more adult-like injuries. Results: The most common cause of injury is blunt trauma. There is an age-related pattern of injuries in pediatric patients. Children under the age of 8 frequently sustain ligamentous injuries in the upper cervical spine. After the age of 8, the biomechanics of the cervical spine are similar to adults, and therefore, bony injuries of the subaxial cervical spine are most likely to occur. Clinical presentation of PCSI is heterogeneous. Younger children can neither interpret nor communicate neurological abnormalities, which make timely and accurate diagnosis difficult. Plain radiographs are often misinterpreted. We find different types of injuries at different locations, because of different biomechanical properties of the immature spine. We outline that initial management is crucial for long-term outcome. Conclusions: Knowledge of biomechanical properties and radiographic presentation of the immature spine can improve the awareness for PCSI. Diagnosis and management of pediatric patients after neck trauma can be demanding. Level of Evidence: Level IV.