Operationalizing and digitizing person-centered daily functioning: a case for functionomics.

An ever-increasing amount of data on a person's daily functioning is being collected, which holds information to revolutionize person-centered healthcare. However, the full potential of data on daily functioning cannot yet be exploited as it is mostly stored in an unstructured and inaccessible manner. The integration of these data, and thereby expedited knowledge discovery, is possible by the introduction of functionomics as a complementary 'omics' initiative, embracing the advances in data science. Functionomics is the study of high-throughput data on a person's daily functioning, that can be operationalized with the International Classification of Functioning, Disability and Health (ICF).A prerequisite for making functionomics operational are the FAIR (Findable, Accessible, Interoperable, and Reusable) principles. This paper illustrates a step by step application of the FAIR principles for making functionomics data machine readable and accessible, under strictly certified conditions, in a practical example. Establishing more FAIR functionomics data repositories, analyzed using a federated data infrastructure, enables new knowledge generation to improve health and person-centered healthcare. Together, as one allied health and healthcare research community, we need to consider to take up the here proposed methods.

Depletion of SNORA33 Abolishes ψ of 28S-U4966 and Affects the Ribosome Translational Apparatus.

Eukaryotic ribosomes are complex molecular nanomachines translating genetic information from mRNAs into proteins. There is natural heterogeneity in ribosome composition. The pseudouridylation (ψ) of ribosomal RNAs (rRNAs) is one of the key sources of ribosome heterogeneity. Nevertheless, the functional consequences of ψ-based ribosome heterogeneity and its relevance for human disease are yet to be understood. Using HydraPsiSeq and a chronic disease model of non-osteoarthritic primary human articular chondrocytes exposed to osteoarthritic synovial fluid, we demonstrated that the disease microenvironment is capable of instigating site-specific changes in rRNA ψ profiles. To investigate one of the identified differential rRNA ψ sites (28S-ψ4966), we generated SNORA22 and SNORA33 KO SW1353 cell pools using LentiCRISPRv2/Cas9 and evaluated the ribosome translational capacity by 35S-Met/Cys incorporation, assessed the mode of translation initiation and ribosomal fidelity using dual luciferase reporters, and assessed cellular and ribosomal proteomes by LC-MS/MS. We uncovered that the depletion of SNORA33, but not SNORA22, reduced 28S-ψ4966 levels. The resulting loss of 28S-ψ4966 affected ribosomal protein composition and function and led to specific changes in the cellular proteome. Overall, our pioneering findings demonstrate that cells dynamically respond to disease-relevant changes in their environment by altering their rRNA pseudouridylation profiles, with consequences for ribosome function and the cellular proteome relevant to human disease.

Local bone metabolism during the consolidation process of spinal interbody fusion.

INTRODUCTION: Although computed tomography (CT) can identify the presence of eventual bony bridges following lumbar interbody fusion (LIF) surgery, it does not provide information on the ongoing formation process of new bony structures. 18F sodium fluoride (18F-NaF) positron emission tomography (PET) could be used as complementary modality to add information on the bone metabolism at the fusion site. However, it remains unknown how bone metabolism in the operated segment changes early after surgery in uncompromised situations. This study aimed to quantify the changes in local bone metabolism during consolidation of LIF. MATERIALS AND METHODS: Six skeletally mature sheep underwent LIF surgery. 18F-NaF PET/CT scanning was performed 6 and 12 weeks postoperatively to quantify the bone volume and metabolism in the operated segment. Bone metabolism was expressed as a function of bone volume. RESULTS: Early in the fusion process, bone metabolism was increased at the endplates of the operated vertebrae. In a next phase, bone metabolism increased in the center of the interbody region, peaked, and declined to an equilibrium state. During the entire postoperative time period of 12 weeks, bone metabolism in the interbody region was higher than that of a reference site in the spinal column. CONCLUSION: Following LIF surgery, there is a rapid increase in bone metabolism at the vertebral endplates that develops towards the center of the interbody region. Knowing the local bone metabolism during uncompromised consolidation of spinal interbody fusion might enable identification of impaired bone formation early after LIF surgery using 18F-NaF PET/CT scanning.

Clavicle lengthening, a novel operation technique to reduce pain in brachial plexus birth injury patients.

BACKGROUND: Brachial plexus birth injury (BPBI) can lead to an imbalance of shoulder musculature that can lead to glenohumeral contractures, and joint and osseous deformities. Glenoid hypoplasia, lengthening of coracoid and acromion, protraction, lateral rotation and elevation of the scapula, and shortening of the clavicle can be observed. As a consequence, the trapezius, levator scapulae, rhomboid, and supraspinatus muscles are overloaded in daily activities causing pain, which can be difficult to treat conservatively. It is hypothesized that operative lengthening of the clavicle may lead to a more anatomic position of the scapula and periscapular muscles, which, as a consequence, may lead to less overloading pain. This study presents the results of this new technique in patients with BPBI. MATERIALS AND METHODS: Seven patients (median age 20 years) were included and underwent a lengthening osteotomy of the clavicle at the affective side. Preoperatively, the osseous deformities were confirmed with a computed tomography scan. Patient-reported outcome measures, Disabilities of Arm, Shoulder and Hand score, and Mallet score were evaluated pre- and postoperatively. RESULTS: After a median of 42 (interquartile range [IQR]: 8.0) months' follow-up, all patients were satisfied with the result. The median numeric rating scale for satisfaction was 8.0 (IQR: 2). Pain decreased from a median numeric rating scale of 7.0 (IQR: 2) preoperatively to 2.0 (IQR: 3) at the final follow-up. The median Mallet score was 14.5 (IQR: 1) preoperatively and 14 (IQR: 0) at the final follow-up. The median Disabilities of Arm, Shoulder and Hand score was 36.7 (IQR: 24.1) at the final follow-up. All patients returned to their normal work without changes in working conditions. CONCLUSION: Short-term follow-up shows that in patients with BPBI with a short clavicle at the affected side and malposition of the scapula, a lengthening osteotomy of the clavicle is a safe and promising technique to reduce pain based on overloading, without deterioration of shoulder function.

The antiviral protein viperin regulates chondrogenic differentiation via CXCL10 protein secretion.

Viperin (also known as radical SAM domain-containing 2 (RSAD2)) is an interferon-inducible and evolutionary conserved protein that participates in the cell's innate immune response against a number of viruses. Viperin mRNA is a substrate for endoribonucleolytic cleavage by RNase mitochondrial RNA processing (MRP) and mutations in the RNase MRP small nucleolar RNA (snoRNA) subunit of the RNase MRP complex cause cartilage-hair hypoplasia (CHH), a human developmental condition characterized by metaphyseal chondrodysplasia and severe dwarfism. It is unknown how CHH-pathogenic mutations in RNase MRP snoRNA interfere with skeletal development, and aberrant processing of RNase MRP substrate RNAs is thought to be involved. We hypothesized that viperin plays a role in chondrogenic differentiation. Using immunohistochemistry, real-time quantitative PCR, immunoblotting, ELISA, siRNA-mediated gene silencing, plasmid-mediated gene overexpression, label-free MS proteomics, and promoter reporter bioluminescence assays, we discovered here that viperin is expressed in differentiating chondrocytic cells and regulates their protein secretion and the outcome of chondrogenic differentiation by influencing transforming growth factor ß (TGF-ß)/SMAD family 2/3 (SMAD2/3) activity via C-X-C motif chemokine ligand 10 (CXCL10). Of note, we observed disturbances in this viperin-CXCL10-TGF-ß/SMAD2/3 axis in CHH chondrocytic cells. Our results indicate that the antiviral protein viperin controls chondrogenic differentiation by influencing secretion of soluble proteins and identify a molecular route that may explain impaired chondrogenic differentiation of cells from individuals with CHH.

Gait in patients with symptomatic osteoporotic vertebral compression fractures over 6 months of recovery.

BACKGROUND: One factor related to disability in people with spinal deformity is decreased postural control and increased risk of falling. However, little is known about the effect of osteoporotic vertebral compression fractures (OVCFs) and their recovery on gait and stability. Walking characteristics of older adults with and without vertebral fractures have not yet been compared. AIMS: The purpose of the current study was to examine the spatiotemporal gait parameters and their variability in patients with an OVCF and healthy participants during treadmill walking at baseline and after 6 months of recovery. METHODS: Twelve female patients suffering a symptomatic OVCF were compared to 11 matched controls. Gait analysis was performed with a dual-belt instrumented treadmill with a 180° projection screen providing a virtual environment (computer-assisted rehabilitation environment). Results of patients with an OVCF and healthy participants were compared. Furthermore, spatiotemporal gait parameters were assessed over 6 months following the fracture. RESULTS: Patients suffering from an OVCF appeared to walk with significantly shorter, faster and wider strides compared to their healthy counterparts. Although stride time and length improved over time, the majority of the parameters analysed remained unchanged after 6 months of conservative treatment. DISCUSSION: Since patients do not fully recover to their previous level of mobility after 6 months of conservative treatment for OVCF, it appears of high clinical importance to add balance and gait training to the treatment algorithm of OVCFs. CONCLUSIONS: Patients suffering from an OVCF walk with shorter, faster and wider strides compared to their healthy counterparts adopt a less stable body configuration in the anterior direction, potentially increasing their risk of forward falls if perturbed. Although stride time and stride length improve over time even reaching healthy levels again, patients significantly deviate from normal gait patterns (e.g. in stability and step width) after 6 months of conservative treatment.

Chondroprotective Actions of Selective COX-2 Inhibitors In Vivo: A Systematic Review.

Knee osteoarthritis (OA) is a condition mainly characterized by cartilage degradation. Currently, no effective treatment exists to slow down the progression of OA-related cartilage damage. Selective COX-2 inhibitors may, next to their pain killing properties, act chondroprotective in vivo. To determine whether the route of administration is important for the efficacy of the chondroprotective properties of selective COX-2 inhibitors, a systematic review was performed according to the PRISMA guidelines. Studies investigating OA-related cartilage damage of selective COX-2 inhibitors in vivo were included. Nine of the fourteen preclinical studies demonstrated chondroprotective effects of selective COX-2 inhibitors using systemic administration. Five clinical studies were included and, although in general non-randomized, failed to demonstrate chondroprotective actions of oral selective COX-2 inhibitors. All of the four preclinical studies using bolus intra-articular injections demonstrated chondroprotective actions, while one of the three preclinical studies using a slow release system demonstrated chondroprotective actions. Despite the limited evidence in clinical studies that have used the oral administration route, there seems to be a preclinical basis for considering selective COX-2 inhibitors as disease modifying osteoarthritis drugs when used intra-articularly. Intra-articularly injected selective COX-2 inhibitors may hold the potential to provide chondroprotective effects in vivo in clinical studies.

Limited predictive value of pre-surgical level of functioning for functioning at 3 and 12 months after TKA.

PURPOSE: A total knee arthroplasty (TKA) is a cost-effective option to relieve pain and improve knee function in patients suffering from osteoarthritis. However, results differ among patients. The predictive value of pre-surgically assessed factors on the level of functioning after 3 and 12 months was investigated in this study. METHODS: This study used an inception cohort design and a follow-up of 12 months. One hundred and fifty patients who were to receive a TKA were assessed pre-surgically with an International Classification of Functioning, Disability and Health (ICF) core assessment set: Knee Society Score (KSS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Short-Form 12 (SF12), Patient-Specific Function Scale (PSFS), range of motion (ROM), quadriceps and hamstring strength and gait parameters. The main outcome measure was WOMAC-Function at 3 and 12 months after surgery. RESULTS: Pre-surgical physical and mental health on the SF12 and functioning and stiffness on the WOMAC explained 23% of the variance in the level of functioning 3 months after surgery. Pre-surgical knee function measured with the KSS-Knee, and functioning as assessed by WOMAC-Function explained 16% of the variance of the level of functioning 12 months after surgery. CONCLUSIONS: The results of this study show that better functioning before surgery, less knee stiffness and a better physical and mental health to some extent predict better functioning 3 months after surgery. This effect is less evident at 12 months. This study is clinically relevant since it provides benchmark data for health care providers who want to compare their individual patients. LEVEL OF EVIDENCE: II.

Reduction of intradiscal pressure by the use of polycarbonate-urethane rods as compared to titanium rods in posterior thoracolumbar spinal fixation.

Loss of sagittal alignment and balance in adult spinal deformity can cause severe pain, disability and progressive neurological deficit. When conservative treatment has failed, spinal fusion using rigid instrumentation is currently the salvage treatment to stop further curve progression. However, fusion surgery is associated with high revision rates due to instrumentation failure and proximal junctional failure, especially if patients also suffer from osteoporosis. To address these drawbacks, a less rigid rod construct is proposed, which is hypothesized to provide a more gradual transition of force and load distribution over spinal segments in comparison to stiff titanium rods. In this study, the effect of variation in rod stiffness on the intradiscal pressure (IDP) of fixed spinal segments during flexion-compression loading was assessed. An ex vivo multisegment (porcine) flexion-compression spine test comparing rigid titanium rods with more flexible polycarbonate-urethane (PCU) rods was used. An increase in peak IDP was found for both the titanium and PCU instrumentation groups as compared to the uninstrumented controls. The peak IDP for the spines instrumented with the PCU rods was significantly lower in comparison to the titanium instrumentation group. These results demonstrated the differences in mechanical load transfer characteristics between PCU and titanium rod constructs when subjected to flexion-compression loading. The concept of stabilization with a less rigid rod may be an alternative to fusion with rigid instrumentation, with the aim of decreasing mechanical stress on the instrumented segments and the possible benefit of a decrease in the incidence of screw pullout.

Tibial component rotation in total knee arthroplasty.

BACKGROUND: Both the range of motion (ROM) technique and the tibial tubercle landmark (TTL) technique are frequently used to align the tibial component into proper rotational position during total knee arthroplasty (TKA). The aim of the study was to assess the intra-operative differences in tibial rotation position during computer-navigated primary TKA using either the TTL or ROM techniques. The ROM technique was hypothesized to be a repeatable method and to produce different tibial rotation positions compared to the TTL technique. METHODS: A prospective, observational study was performed to evaluate the antero-posterior axis of the cut proximal tibia using both the ROM and the TTL technique during primary TKA without postoperative clinical assessment. Computer navigation was used to measure this difference in 20 consecutive knees of 20 patients who underwent a posterior stabilized total knee arthroplasty with a fixed-bearing polyethylene insert and a patella resurfacing. RESULTS: The ROM technique is a repeatable method with an interclass correlation coefficient (ICC2) of 0.84 (p < 0.001). The trial tibial baseplate was on average 4.56 degrees externally rotated compared to the tubercle landmark. This difference was statistically significant (p = 0.028). The amount of maximum intra-operative flexion and the pre-operative mechanical axis were positively correlated with the magnitude of difference between the two methods. CONCLUSIONS: It is important for the orthopaedic surgeon to realise that there is a significant difference between the TTL technique and ROM technique when positioning the tibial component in a rotational position. This difference is correlated with high maximum flexion and mechanical axis deviations.

EGR1 controls divergent cellular responses of distinctive nucleus pulposus cell types.

BACKGROUND: Immediate early genes (IEGs) encode transcription factors which serve as first line response modules to altered conditions and mediate appropriate cell responses. The immediate early response gene EGR1 is involved in physiological adaptation of numerous different cell types. We have previously shown a role for EGR1 in controlling processes supporting chondrogenic differentiation. We recently established a unique set of phenotypically distinct cell lines from the human nucleus pulposus (NP). Extensive characterization showed that these NP cellular subtypes represented progenitor-like cell types and more functionally mature cells. METHODS: To further understanding of cellular heterogeneity in the NP, we analyzed the response of these cell subtypes to anabolic and catabolic factors. Here, we test the hypothesis that physiological responses of distinct NP cell types are mediated by EGR1 and reflect specification of cell function using an RNA interference-based experimental approach. RESULTS: We show that distinct NP cell types rapidly induce EGR1 exposure to either growth factors or inflammatory cytokines. In addition, we show that mRNA profiles induced in response to anabolic or catabolic conditions are cell type specific: the more mature NP cell type produced a strong and more specialized transcriptional response to IL-1ß than the NP progenitor cells and aspects of this response were controlled by EGR1. CONCLUSIONS: Our current findings provide important substantiation of differential functionality among NP cellular subtypes. Additionally, the data shows that early transcriptional programming initiated by EGR1 is essentially restrained by the cells' epigenome as it was determined during development and differentiation. These studies begin to define functional distinctions among cells of the NP and will ultimately contribute to defining functional phenotypes within the adult intervertebral disc.

How to follow up patients with brachial plexus birth palsy in the long term: a survey of expert opinion.

There is no generally accepted diagnostic, treatment and follow-up algorithm for brachial plexus birth palsy in the current literature. This study evaluates the opinion of experts in the field of brachial plexus birth palsy surgery, to provide a follow-up guideline. A total of 35 experts attending an international meeting with a mean of 21.5 years (SD 10.1) of experience in the field filled out a questionnaire to evaluate the following: (1) the surgeons' background; (2) clinical follow-up; (3) radiological follow-up; and (4) International Classification of Functioning, Disability and Health (ICF) domains. A mean of 40 new brachial plexus birth palsy patients were seen per year by each expert, of which 36% needed surgery. In total, 27 experts scheduled a regular follow-up every year and the majority (83%) believed that standardized long-term clinical follow-up is necessary. However, standardized radiological follow-up is not necessary. Only 13 of 34 participants used patient-reported outcome measures to investigate ICF domains.Level of evidence: V.

The BMP7-Derived Peptide p[63-82] Reduces Cartilage Degeneration in the Rat ACLT-pMMx Model for Posttraumatic Osteoarthritis.

OBJECTIVE: Osteoarthritis (OA) is characterized by articular cartilage erosion, pathological subchondral bone changes, and signs of synovial inflammation and pain. We previously identified p[63-82], a bone morphogenetic protein 7 (BMP7)-derived bioactive peptide that attenuates structural cartilage degeneration in the rat medial meniscal tear-model for posttraumatic OA. This study aimed to evaluate the cartilage erosion-attenuating activity of p[63-82] in a different preclinical model for OA (anterior cruciate ligament transection-partial medial meniscectomy [anterior cruciate ligament transection (ACLT)-pMMx]). The disease-modifying action of the p[63-82] was followed-up in this model for 5 and 10 weeks. DESIGN: Skeletally mature male Lewis rats underwent ACLT-pMMx surgery. Rats received weekly intra-articular injections with either saline or 500 ng p[63-82]. Five and 10 weeks postsurgery, rats were sacrificed, and subchondral bone characteristics were determined using microcomputed tomography (µCT). Histopathological evaluation of cartilage degradation and Osteoarthritis Research Society International (OARSI)-scoring was performed following Safranin-O/Fast Green staining. Pain-related behavior was measured by incapacitance testing and footprint analysis. RESULTS: Histopathological evaluation at 5 and 10 weeks postsurgery showed reduced cartilage degeneration and a significantly reduced OARSI score, whereas no significant changes in subchondral bone characteristics were found in the p[63-82]-treated rats compared to the saline-treated rats. ACLT-pMMx-induced imbalance of static weightbearing capacity in the p[63-82] group was significantly improved compared to the saline-treated rats at weeks 5 postsurgery. Footprint analysis scores in the p[63-82]-treated rats demonstrated improvement at week 10 postsurgery. CONCLUSIONS: Weekly intra-articular injections of p[63-82] in the rat ACLT-pMMx posttraumatic OA model resulted in reduced degenerative cartilage changes and induced functional improvement in static weightbearing capacity during follow-up.

Autologous engineering of cartilage.

Treatment of full-thickness damage to hyaline cartilage is hampered by the limited availability of autologous healthy cartilage and the lengthy, cost-prohibitive cell isolation and expansion steps associated with autologous cartilage implantation (ACI). Here we report a strategy for de novo engineering of ectopic autologous cartilage (EAC) within the subperiosteal space (in vivo bioreactor), through the mere introduction of a biocompatible gel that might promote hypoxia-mediated chondrogenesis, thereby effectively overcoming the aforementioned limitations. The EAC is obtained within 3 wk post injection of the gel, and can be press-fit into an osteochondral defect where it undergoes remodeling with good lateral and subchondral integration. The implanted EAC showed no calcification even after 9 mo and attained an average O'Driscoll score of 11 (versus 4 for controls). An "on demand" autologous source of autologous cartilage with remodeling capacity is expected to significantly impact the clinical options in repair of trauma to articular cartilage.

Transhumeral amputation in brachial plexus lesion patients: A multicenter case series.

BACKGROUND: A flail limb can be the result of a traumatic complete brachial plexus lesion. Some patients prefer retaining the flail limb, however some patients feel that a flail limb negatively affects daily life. In these circumstances an elective amputation is sometimes elected, however long-term follow-up, with respect to satisfaction and function is unknown. The aim of this study is to evaluate the long-term outcome of this rare and life changing operation. MATERIALS AND METHODS: 8 patients with a transhumeral amputation performed in 2 specialized medical centers were included. Postoperatively, the functional- and psychological outcome and the quality of life were evaluated with standardized patient reported outcome measures (PROMs; DASH, SIP-68, EQ-5D-5L and HADS). RESULTS: After a median of 9.4 (range 7.5 - 12.8) years follow-up, 7 patients (88%) stated that they would undergo the operation again and were satisfied with the results. At latest follow-up the median DASH score was 37.3 (range 8.3-61.7), the median SIP-68 score was 6.5 (range 0-43) and the median HADS score was 3.0 (range 0-14) for anxiety and 3.0 (range 1-19) for depression. In the EQ-5D-5L patients had most difficulties in self-care, usual activities and pain/discomfort. The median overall health status was 69 (range 20-95). DISCUSSION: With the right indication a transhumeral amputation is a reasonable option for traumatic complete brachial plexus lesion with satisfying long-term results. LEVEL OF EVIDENCE: IV, multicenter case series.

Alignment of CCI total ankle replacements in relation to midterm functional outcome and complication incidence.

BACKGROUND: Total ankle arthroplasty is increasingly used as a treatment for end stage ankle arthropathy. The aim of this study was to report the mid-term clinical function and survival results of Ceramic Coated Implant (CCI) ankle replacements and assess the association between the alignment of the CCI total ankle replacements and early functional outcome and complication incidence. METHODS: Data of 61 patients, who received 65 CCI implants between 2010 and 2016, were obtained from a prospectively documented database. Mean follow-up time was 85.2 months (range 27-99 months). Clinical function was assessed with AOFAS questionnaire and passive range of motion (ROM). Survival analysis and elaborate radiographic analysis was performed. Furthermore, complications and reoperations were recorded for all patients. RESULTS: Progression in ROM was most seen in the first 10 months from 21.8 degrees of passive range of motion preoperative to 27.6 degrees postoperative (p < 0.001), while the mean AOFAS gradually increased during follow-up postoperative from a mean of 40.9 points preoperative to an average of 82.5 but shows a small decline towards the end of follow-up (p < 0.001). During follow-up we recorded 8 failures (12.3%) resulting in a Kaplan-Meier survival analysis of 87.7% with a median follow-up of 85.2 months. CONCLUSION: We observed excellent clinical results and survival after TAA with the CCI implant with only a low mid-term complication rate. LEVEL OF EVIDENCE: Level III, prospective cohort study.

[Network medicine for people with movement complaints in the Netherlands: the Beweeghuis and other orthopaedic initiatives]. / Netwerkgeneeskunde voor mensen met beweegklachten.

The prevalence of disorders related to the movement apparatus such as osteoarthritis and neck/back complaints is increasing, thereby compromising the accessibility and affordability of movement care. Besides, these complaints cause high burden of disease, high sick leave and decreased self-sustainability. These developments demand an integral multidisciplinary and line transcending approach. Within the field of movement care several initiatives are already developed such as the Beweeghuis Network, Network Osteoarthritis, One-and-a-half line outpatient clinic Zuyderland. If healthcare evaluation of these initiatives show positive effects, these examples of network medicine can give answer and substance to the challenges and assignments discussed in the Integral Care Act. An important condition for upscaling on a national level is a new funding model in which prevention of care is being rewarded as well.

Long-term functional outcome of secondary shoulder surgery in brachial plexus birth palsy patients.

Multiple secondary surgical procedures of the shoulder, such as soft-tissue releases, tendon transfers, and osteotomies, are described in brachial plexus birth palsy (BPBP) patients. The long-term functional outcomes of these procedures described in the literature are inconclusive. We aimed to analyze the literature looking for a consensus on treatment options. A systematic literature search in healthcare databases (PubMed, Embase, the Cochrane library, CINAHL, and Web of Science) was performed from January 2000 to July 2020, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. The quality of the included studies was assessed with the Cochrane ROBINS-I risk of bias tool. Relevant trials studying BPBP with at least five years of follow-up and describing functional outcome were included. Of 5,941 studies, 19 were included after full-text screening. A total of 15 surgical techniques were described. All studies described an improvement in active external rotation (range 12° to 128°). A decrease in range of motion and Mallet score after long-term (five to 30 years) follow-up compared to short-term follow-up was seen in most studies. The literature reveals that functional outcome increases after different secondary procedures, even in the long term. Due to the poor methodological quality of the included studies and the variations in indication for surgery and surgical techniques described, a consensus on the long-term functional outcome after secondary surgical procedures in BPBP patients cannot be made.

Clinical, radiological, histological and retrieval findings of Activ-L and Mobidisc total disc replacements: a study of two patients.

INTRODUCTION: This study evaluates the short-term clinical outcome, radiological, histological and device retrieval findings of two patients with second generation lumbar total disc replacement (TDR). MATERIALS AND METHODS: The first patient had a single level L4-L5 Activ-L TDR, the second patient a L4-L5 Mobidisc and L5-S1 Activ-L TDR. The TDRs were implanted elsewhere and had implantation times between 1.3 and 2.8 years. RESULTS: Plain radiographs and CT-scanning showed slight subsidence of the Activ-L TDR in both patients and facet joint degeneration. The patients underwent revision surgery because of recurrent back and leg pain. After removal of the TDR and posterolateral fusion, the pain improved. Histological examination revealed large ultrahigh molecular weight polyethylene (UHMWPE) particles and giant cells in the retrieved tissue surrounding the Mobidisc. The particles in the tissue samples of the Activ-L TDR were smaller and contained in macrophages. Retrieval analysis of the UHMWPE cores revealed evidence of minor adhesive and abrasive wear with signs of impingement in both TDR designs. CONCLUSION: Although wear was unrelated to the reason for revision, this study demonstrates the presence of UHMWPE particles and inflammatory cells in second generation TDR. Long-term follow-up after TDR is indicated for monitoring wear and implant status.

The humeral suspension technique: a novel operation for deltoid paralysis.

Isolated deltoid paralysis is a rare pathology that can occur after axillary nerve injury due to shoulder trauma or infection. This condition leads to loss of deltoid function that can cause glenohumeral instability and inferior subluxation, resulting in rotator cuff muscle fatigue and pain. To establish dynamic glenohumeral stability, a novel technique was invented. Humeral suspension is achieved using a double button implant with non-resorbable high strength cords between the acromion and humeral head. This novel technique was used in two patients with isolated deltoid paralysis due to axillary nerve injury. The results indicate that the humeral suspension technique is a method that supports centralizing the humeral head and simultaneously dynamically stabilizes the glenohumeral joint. This approach yielded high patient satisfaction and reduced pain. Glenohumeral alignment was improved and remained intact 5 years postoperative. The humeral suspension technique is a promising surgical method for subluxated glenohumeral joint instability due to isolated deltoid paralysis.