Can spinopelvic mobility be predicted in patients awaiting total hip arthroplasty? A prospective, diagnostic study of patients with end-stage hip osteoarthritis.

AIMS: This study of patients with osteoarthritis (OA) of the hip aimed to: 1) characterize the contribution of the hip, spinopelvic complex, and lumbar spine when moving from the standing to the sitting position; 2) assess whether abnormal spinopelvic mobility is associated with worse symptoms; and 3) identify whether spinopelvic mobility can be predicted from static anatomical radiological parameters. PATIENTS AND METHODS: A total of 122 patients with end-stage OA of the hip awaiting total hip arthroplasty (THA) were prospectively studied. Patient-reported outcome measures (PROMs; Oxford Hip Score, Oswestry Disability Index, and Veterans RAND 12-Item Health Survey Score) and clinical data were collected. Sagittal spinopelvic mobility was calculated as the change from the standing to sitting position using the lumbar lordosis angle (LL), sacral slope (SS), pelvic tilt (PT), pelvic-femoral angle (PFA), and acetabular anteinclination (AI) from lateral radiographs. The interaction of the different parameters was assessed. PROMs were compared between patients with normal spinopelvic mobility (10° ≤ ∆PT ≤ 30°) or abnormal spinopelvic mobility (stiff: ∆PT < ± 10°; hypermobile: ∆PT > ± 30°). Multiple regression and receiver operating characteristic (ROC) curve analyses were used to test for possible predictors of spinopelvic mobility. RESULTS: Standing to sitting, the hip flexed by a mean of 57° (sd 17°), the pelvis tilted backwards by a mean of 20° (sd 12°), and the lumbar spine flexed by a mean of 20° (sd 14°); strong correlations were detected. There was no difference in PROMs between patients in the different spinopelvic mobility groups. Maximum hip flexion, standing PT, and standing AI were independent predictors of spinopelvic mobility (R2 = 0.42). The combined thresholds for standing was PT ≥ 13° and hip flexion ≥ 88° in the clinical examination, and had 90% sensitivity and 63% specificity of predicting spinopelvic stiffness, while SS ≥ 42° had 84% sensitivity and 67% specificity of predicting spinopelvic hypermobility. CONCLUSION: The hip, on average, accounts for three-quarters of the standing-to-sitting movement, but there is great variation. Abnormal spinopelvic mobility cannot be screened with PROMs. However, clinical and standing radiological features can predict spinopelvic mobility with good enough accuracy, allowing them to be used as reliable screening tools. Cite this article: Bone Joint J 2019;101-B:902-909.

Knock-down of oncohistone H3F3A-G34W counteracts the neoplastic phenotype of giant cell tumor of bone derived stromal cells.

Giant cell tumors of bone (GCTB) are semi-malignant tumors associated with extensive osteolytic defects and massive bone destructions. They display a locally aggressive behavior and a very high recurrence rate. Recently, a single mutation has been identified in GCTB affecting the H3F3A gene coding for the histone variant H3.3 (H3.3-G34W). The aim of this study was to investigate whether H3.3-G34W is sufficient to drive tumorigenesis in GCTB. Initially, we confirmed the high frequency of this mutation in 94% of 84 analyzed tissue samples. Using a siRNA based approach we could selectively knockdown H3.3-G34W in primary neoplastic stromal cells isolated from tumor tissue (GCTSC). H3.3-G34W knockdown caused a significant inhibition of cell proliferation, migration and colony formation capacity in vitro. Xenotransplantation of GCTSCs onto the chorioallantoic membrane of fertilized chicken eggs further demonstrated a significant impact of H3.3-G34W knockdown on tumor engraftment and growth in vivo. Our data indicate that H3.3-G34W is sufficient to drive tumorigenesis in GCTB. Apart from the application of H3.3-G34W screening as diagnostic tool, our data suggest that H3.3-G4W represents a promising target for the development of new GCTB therapies.

[Modular Neck in Primary Total Hip Replacement--A Justifiable Risk?]. / Modulare Primärendoprothetik--Risiko gerechtfertigt?

Modular necks are considered as a treatment option in primary total hip replacement aiming to allow a variable reconstruction of the hip joint. Concerns are related to increased failure and complication rates which may be associated with the additional modular interface. This interface is frequently affected by corrosion processes which may initiate premature failure of the entire implant. In this study the risk of modular necks as a clinical treatment option is evaluated. Based on register data and clinical studies modular necks should only be used with strict limitations for general treatment in primary total hip replacement.

Radiation Dose Reduction in Digital Plain Radiography of the Knee after Total Knee Arthroplasty.

PURPOSE: To reduce radiation exposure of frequently performed radiographs of the knee in follow-up of total-knee arthroplasty ensuring accurate assessment by using objective quality control criteria. MATERIALS AND METHODS: In this prospective randomized study 278 radiographs of the knee in follow-up of total-knee arthroplasty were performed with standard and 37% reduced radiation dose. The evaluation of the plain-radiographs was conducted using the following criteria: bone-implant interface, implant-surface character, implant-implant discrimination and periarticular heterotopic ossification. Two radiologists evaluated these criteria using a score ranging from 1 (definitely assessable) to 4 (not assessable). If a single criterion had been evaluated with a score ≥ 3 or more than 2 criteria with ≥ 2 points, the radiograph was score das "not assessable". The study was designed as non-inferiority-trial. RESULTS: 100% of examined radiographs were scored as assessable, hence no statistical inferiority between the examinations with standard and reduced dose could be observed. Singular assessment of the defined criteria was likewise dose-independent. CONCLUSION: Plain-radiography of the knee following total-knee arthroplasty can be performed with 63% of standard dose without loss of diagnostic validity. KEY POINTS: Due to the non-inferiority of digital radiographs of the knee joint after total-knee arthroplasty done with 37% reduced image receiver dose we recommend the tested speed class of SC 800 as a new reference value for digital radiographs with this indication.

Distal Rectus Femoris Tendon Transfer for the Correction of Stiff-Knee Gait in Cerebral Palsy.

INTRODUCTION: Distal rectus femoris tendon transfer is the standard surgical procedure for the treatment of stiff-knee gait in patients with cerebral palsy and is commonly performed during single-event multilevel surgery. STEP 1 POSITIONING AND APPROACH: With the patient supine, make a 3 to 4-cm longitudinal incision 2 to 3 cm above the patellar proximal pole. STEP 2 PREPARATION OF THE RECTUS FEMORIS TENDON: Separate the rectus femoris tendon from the vasti; avoid releasing the entire quadriceps at all cost. STEP 3 PREPARATION OF THE GRACILIS OR SEMITENDINOSUS TENDON FOR TRANSFER: Isolate the gracilis tendon proximally, release it from its muscle belly, and pull it out distally through a small incision at the pes anserinus insertion. STEP 4 TRANSFERRING THE GRACILIS TENDON TO THE RECTUS FEMORIS TENDON: Insert a long tendon passer above the fascia and beneath the sartorius muscle belly from anterior to posterior to the mini-incision in the pes anserinus region to grasp and transfer the gracilis tendon to the anterior approach. STEP 5 TENDON TENSIONING AND SUTURING: Weave the gracilis tendon into the released rectus femoris tendon with the interlacing technique described by Pulvertaft. RESULTS: Various studies have demonstrated good initial results, with an improvement in peak knee flexion in swing phase and knee motion in swing phase, following distal rectus femoris tendon transfer. WHAT TO WATCH FOR: IndicationsContraindicationsPitfalls & Challenges.

Pigmented villo-nodular synovitis and giant-cell tumor of tendon sheaths: a binational retrospective study.

AIM: Pigmented villonodular synovitis is rare. Thus, we initiated a retrospective multi-center study regarding symptoms, location, type of disease, type of surgery, number of recurrences, use of adjuvant therapies and functional outcome. RESULTS: Ten centers contributed. Data from 173 patients were sampled. The disease was seen predominantly in joints, less frequently in tendon sheaths and bursae. Patients with articular lesions suffered mainly from the diffuse type. In tendon sheaths, the relation "diffuse versus nodular" was nearly 50 % each, in bursae most often the nodular type was found. Anatomically, mostly the knee was affected. Institutions with more than 20 patients had a lower rate of recurrence than those with less than 20 cases. Regarding the knee, there were less recurrences in joints treated with open synovectomy than in those treated arthroscopically. CONCLUSIONS: Since the rate of recurrence has been rather high, the use of adjuvant treatments (radiosynoviorthesis or radiotherapy) is recommended. In our study, the rate of their application was quite low. Patients who received an adjuvant therapy after primary surgery did not show any recurrence. In 14 % of patients in whom an adjuvant therapy had been used, after at least one recurrence, further recurrences were observed. Functional results were excellent in 84 % of patients. LEVEL OF EVIDENCE: Prognostic multi-center study, Level III.

[Modern digital plain-radiography of the whole spine in scoliosis patients--dose reduction and quality criteria]. / Moderne digitale Radiografie der Ganzwirbelsäule bei Skoliose - Dosisreduktion und Qualitätskriterien.

PURPOSE: To reduce the radiation exposure of plain radiographs of the entire spine depending on specific indications, since these are frequently performed examinations of children and young adults with scoliosis and to determine objective quality control criteria to ensure accurate assessment. MATERIALS AND METHODS: In this prospective randomized study 323 patients underwent plain-radiography of the entire spine with standard and 50 % reduced dose. In an experimental pilot-study this target-dose was determined using an Alderson-Phantom. The evaluation of the experimental radiographs, as well as, the randomized plain-radiographs was conducted using the following criteria: endplates (Cobb-angle), spinal process and pedicel (rotation), lateral margin of the vertebral body (lateral alignment), identification of C7 / S1 (perpendicular). Two radiologists evaluated these criteria using a score ranging from 1 (definitely assessable) to 4 (not assessable). If one single criteria was evaluated with a score of 3 or more points or more than 2 criteria with 2 points, the radiograph was scored as "not assessable". The statistical analysis was conducted as a non-inferiority-trial. RESULTS: Seven (2.4 %) of the 290 examined x-rays were scored as not assessable. There was no statistic inferiority between the examinations with standard or reduced dose, while singular assessment of the defined criteria was likewise dose-independent. CONCLUSION: Plain-radiography of the total spine in patients with scoliosis can be performed with a dose reduction of 50% without a loss of validity. The obtained quality control criteria were clinically applicable.

Motion capture of the upper extremity during activities of daily living in patients with spastic hemiplegic cerebral palsy.

Investigations using motion capture to analyze limitations in range of motion (ROM) of the upper extremity in adults with cerebral palsy (CP) are scarce. To evaluate the influence of those limitations on activities of daily living (ADL) and to determine potential mechanisms of compensation, we investigated 15 adults with hemiplegic CP using motion capture while they performed 10 defined ADLs. Data from the nonaffected body side and those from an age-matched able-bodied group were also collected and compared with our subjects. We measured motion of the elbow, shoulder, and trunk and found significant differences in ROM at these sites. The most pronounced reduction in ROM was observed distally in supination and pronation of the elbow. Here, the affected body side of the adults showed a reduction in supination of 45° compared to the able-bodied group. Furthermore we found a correlation between the Manual Ability Classification System (MACS) and the limitations in ROM. In summary, adults with spastic, hemiplegic CP show limitations in ROM accentuated distally during ADLs. The MACS gives conclusive information about those limitations.