Shrug radiographs for the diagnosis of long thoracic nerve palsy in traumatic brachial plexus injury.

BACKGROUND: Preoperative diagnosis of long thoracic nerve (LTN) palsy is important for shoulder reconstruction after a traumatic brachial plexus injury (BPI). In the present study, we developed an objective diagnostic method for LTN palsy for patients with traumatic BPI. METHODS: This is a retrospective review of 56 patients with traumatic BPI who had been receiving treatment at a single institution for over 8 years. The patients were divided into 2 groups: an LTN palsy group (n = 30) and a no palsy control group (n = 26). The LTN palsy group had 21 different palsy types with 4 and 5 C5-7 and C5-8, whereas the no palsy group had 18 different palsy types with 5 and 3 C5-6 and C5-8, respectively. Preoperative plain anteroposterior radiographs were taken in shoulder adduction and shrug positions. Scapulothoracic (ST) upward rotation and clavicle lateral (CL) rotation angles were measured on X-rays. The differences between the adduction and shrug positions for the respective angles were calculated and defined as ΦST and ΦCL, respectively. The differences in the ΦST and ΦCL values due to the presence or absence of LTN palsy were examined, the cutoff values of ΦST and ΦCL for the diagnosis of LTN palsy were determined, and further sensitivity and specificity were calculated. RESULTS: Both ΦST and ΦCL were significantly decreased in the LTN palsy group compared with the no palsy control group. The sensitivity and specificity for LTN palsy were 0.833 and 1.000 for ΦST and 0.833 and 0.840 for ΦCL, respectively, when the cutoff value was set as ΦST = 15° and ΦCL ≤ 24°. CONCLUSION: Dynamic shrug radiographs provide a useful objective diagnosis of LTN palsy after traumatic BPI.

The use of dynamic radiographs in trapeziometacarpal joint arthrodesis for accurate range of motion evaluation.

BACKGROUND: Increased motion at the scaphotrapeziotrapezoidal (STT) joint and compensatory hypermobility of metacarpophalangeal (MP) joint contribute to the total abduction and adduction motion of the thumb after trapeziometacarpal (TM) joint arthrodesis. However, there were no detailed studies to evaluate the contribution of motion of each joint towards total thumb mobility. METHODS: We conducted a comparative study on thumb joint motion in 56 hands who underwent TM joint arthrodesis against that of 56 hands in normal subjects. Dynamic radiographs were performed and the angles subtended by the first (M1) and second (M2) metacarpals were to measure radial abduction and adduction, and volar abduction and adduction. In addition, angles subtended by the thumb proximal phalanx (P1) and M1 in abduction and adduction were measured to evaluate the hypermobility of the MP joint. RESULTS: The average total arcs of M1M2 motion in normal subjects in radial and volar abduction-adduction planes were 24° and 35° respectively. The arthrodesis group averaged 9° of motion in the radial abduction and adduction plane and 8° in the volar abduction and adduction plane. P1M1 volar adduction angle was significantly larger in the arthrodesis group, suggesting that the arthrodesis group had larger compensatory motion of the MP joint in volar adduction compared to normal subjects. CONCLUSIONS: These findings on the amount of hypermobility of MP joint after TM joint arthrodesis are valuable information for optimal postoperative rehabilitation protocol. To achieve good range of motion of thumb abduction and adduction following TM joint arthrodesis, emphasis must be placed in obtaining maximum potential motion of STT joint rather than hypermobility of MP joint.

Analysis of shoulder abduction by dynamic shoulder radiograph following suprascapular nerve repair in brachial plexus injury.

BACKGROUND: Suprascapular nerve repair is a widely-prioritized procedure for shoulder reconstruction following brachial plexus injury. Although this procedure only reconstructs glenohumeral joint motion, the standard clinical assessment of shoulder function also includes the scapulothoracic joint contribution. The purpose of this preliminary study was to develop an objective method to accurately analyze shoulder abduction following suprascapular nerve repair in brachial plexus injury patients. METHODS: We introduced an objective method to accurately analyze independent shoulder abduction performed by supraspinatus muscle with the help of dynamic shoulder radiography. Antero-posterior radiographs of both shoulders in adduction and maximal active abduction were obtained. Five parameters were measured. They included global abduction, abduction in glenohumeral, scapulothoracic and clavicular joints along with lateral flexion of thoracic spine. Data were analyzed to distinguish glenohumeral joint contribution from that of scapulothoracic motion. The detailed biomechanics of glenohumeral motion were also analyzed in relation to scapulothoracic motion to separately define the contribution of each in global shoulder abduction. RESULTS: The test-retest, intra-examiner and inter-examiner reliabilities of the measurements were assessed. Intra-class correlation coefficient, Bland-Altman plots and repeatability coefficients showed excellent reliability for each parameter. The range of glenohumeral abduction showed high correlation to subtraction of the range of scapulothoracic from the range of global abduction. However, not all negative ranges of glenohumeral abduction meant non-recovery after nerve repair, because scapulothoracic motion contributed in parallel but not uniformly to global shoulder motion. CONCLUSION: The conventional measurement of shoulder global abduction with goniometer is not an appropriate method to analyze the results of suprascapular nerve repair in brachial plexus palsy patients. We recommend examination of glenohumeral and scapulothoracic motions separately with dynamic shoulder radiographic analysis. With scapulothoracic contribution to the global shoulder motion, the glenohumeral motion can be wrongly assessed.

Novel subtype of coxitis knee associated with acetabular dysplasia of the hip: a case series.

BACKGROUND: Multiple joint arthritis patterns require a comprehensive understanding to optimize patient management. This study aimed to present a patient cohort that deviated from known definitions of coxitis knee (CK), identifying and characterizing this atypical group. METHODS: Patients undergoing both total hip arthroplasty and total knee arthroplasty between January 2008 and December 2018 were retrospectively reviewed. The patients were classified into a typical coxitis knee group (classic, long leg arthropathy, and windswept deformity) and an atypical coxitis knee group. Leg-length discrepancy, body mass index (BMI), and radiographic parameters of the groups were compared and analyzed. RESULTS: A total of 31 patients were allocated to the typical coxitis knee group (n = 10), and atypical coxitis knee group (n = 21). In the atypical group, 27 hips were involved, of which 21 had acetabular dysplasia, 5 exhibited subchondral insufficiency fracture-like changes, and only 1 had classic osteoarthritis. Among the 27 knees undergoing total knee arthroplasty, 26 showed varus alignment, 1 was within the normal range, and none was valgus. Acetabular dysplasia involved ipsilateral (n = 1), contralateral (n = 14), and bilateral (n = 6) hips, showing atypical coxitis knee. Patients with acetabular dysplasia were more likely to exhibit atypical CK. CONCLUSION: Most patients in the cohort displayed acetabular dysplasia and contralateral varus knees, constituting a pattern referred to as acetabular dysplasia-associated gonarthritis. Identifying this novel subtype may have important clinical implications for regions with high risk factors, where acetabular dysplasia and constitutional genu varum are prevalent.

Structural and Functional Alterations of the Deltoid Muscle After Arthroscopic Rotator Cuff Repair: A 2-Year Longitudinal Observation Study.

Background: Deltoid muscle detachment and atrophy have been reported to occur after shoulder surgery. Purpose: To investigate the 2-year changes in deltoid muscle structure and function after arthroscopic rotator cuff repair (ARCR) using magnetic resonance imaging (MRI) and electrophysical examination. Study Design: Case series; Level of evidence, 4. Methods: A total of 72 patients (72 shoulders) who underwent ARCR between 2015 and 2020 were enrolled. Whole deltoid muscle volume and regional (anterior, lateral, and posterior) muscle thicknesses were determined on T2-weighted MRI scans of both shoulders taken preoperatively and at 1, 3, 6, 12, and 24 months postoperatively, and their correlations with compound muscle action potentials (CMAPs), shoulder abduction muscle strength, and Constant scores were investigated. Comparison between groups was performed using paired or Student t tests, and the relationship between deltoid muscle volume and various factors was determined using Pearson correlation analysis. Results: The volume of the deltoid muscle on the affected side decreased from 44,369 ± 12,371 mm3 preoperatively to 38,139 ± 10,615 mm3 at 1 month postoperatively (P < .05), representing a 14% decrease. The deltoid muscle volume of the contralateral side also significantly decreased during the same time frame, from 43,278 ± 12,248 to 40,273 ± 11,464 mm3 (P < .05), representing a 7% decrease at 1 month postoperatively. Subsequently, the deltoid muscle volume on both sides recovered to preoperative levels at 12 months and was maintained at 24 months. Only the thickness of the anterior part of the deltoid was markedly decreased, from 13.9 ± 3.7 mm preoperatively to 12.0 ± 3.2 mm at 1 month postoperatively (P < .05), representing a 14% reduction. The CMAP amplitude showed a significant decrease at 1 month postoperatively; however, no significant difference was observed after 12 months when compared with the preoperative values or the values on the contralateral side. Positive correlations were found between deltoid muscle volume and CMAP amplitude at 24 months as well as between deltoid muscle volume and shoulder abduction muscle strength (R 2 = 0.698; P < .05) and Constant score (R 2 = 0.133; P < .05). Conclusion: Our study demonstrated that the early structural and functional decline of the deltoid muscle after ARCR was fully recovered within 1 year, confirming that this procedure does not negatively affect the deltoid muscle.

Early changes in muscle atrophy and muscle fiber type conversion after spinal cord transection and peripheral nerve transection in rats.

BACKGROUND: Spinal cord transection and peripheral nerve transection cause muscle atrophy and muscle fiber type conversion. It is still unknown how spinal cord transection and peripheral nerve transection each affect the differentiation of muscle fiber type conversion mechanism and muscle atrophy. The aim of our study was to evaluate the difference of muscle weight change, muscle fiber type conversion, and Peroxisome proliferator-activated receptor-γ coactivatior-1α (PGC-1α) expression brought about by spinal cord transection and by peripheral nerve transection. METHODS: Twenty-four Wistar rats underwent surgery, the control rats underwent a laminectomy; the spinal cord injury group underwent a spinal cord transection; the denervation group underwent a sciatic nerve transection. The rats were harvested of the soleus muscle and the TA muscle at 0 week, 1 week and 2 weeks after surgery. Histological examination was assessed using hematoxylin and eosin (H&E) staining and immunofluorescent staing. Western blot was performed with 3 groups. RESULTS: Both sciatic nerve transection and spinal cord transection caused muscle atrophy with the effect being more severe after sciatic nerve transection. Spinal cord transection caused a reduction in the expression of both sMHC protein and PGC-1α protein in the soleus muscle. On the other hand, sciatic nerve transection produced an increase in expression of sMHC protein and PGC-1α protein in the soleus muscle. The results of the expression of PGC-1α were expected in other words muscle atrophy after sciatic nerve transection is less than after spinal cord transection, however muscle atrophy after sciatic nerve transection was more severe than after spinal cord transection. CONCLUSION: In the conclusion, spinal cord transection diminished the expression of sMHC protein and PGC-1α protein in the soleus muscle. On the other hand, sciatic nerve transection enhanced the expression of sMHC protein and PGC-1α protein in the soleus muscle.

Neutrophil-, Monocyte- and Platelet-to-Lymphocyte Ratios, and Absolute Lymphocyte Count for Diagnosis of Malignant Soft-tissue Tumors.

BACKGROUND/AIM: Soft-tissue tumors are difficult to differentiate as benign or malignant. Immune markers, such as the neutrophil-lymphocyte ratio (NLR), monocyte-lymphocyte ratio (MLR), platelet-lymphocyte ratio (PLR), and absolute lymphocyte count (ALC) in serum, have been reported to be useful in the diagnosis and predicting prognosis of several malignancies. We investigated the diagnostic value of these immune markers in differentiating soft-tissue tumors. PATIENTS AND METHODS: A total of 692 patients who underwent biopsy or surgery of soft-tissue tumors were included and divided into benign tumor, low-grade malignancy, or high-grade malignancy groups. Immune markers were calculated from the preoperative blood tests and compared between the groups. A receiver operating curve (ROC) analysis was conducted between the benign disease group and a combination of the groups with malignancy to determine which immune marker had the most diagnostic value. RESULTS: NLR and MLR were significantly different between the three groups with benign disease having the lowest value and high-grade malignancies the highest. Benign disease was also associated with lower PLR and higher ALC. There was no difference between the low- and high-grade malignancies in PLR and ALC. From the ROC analysis, NLR had the highest area under the curve (AUC) value of 0.773 out of the four markers. When limited to small tumors (≤30 mm), NLR had the highest AUC value of 0.729. CONCLUSION: The NLR showed the highest diagnostic value, although the diagnostic ability was not adequately high to differentiate benign and malignant soft-tissue tumors alone. NLR may serve as diagnostic support in combination with clinical history, physical findings, and tumor-imaging results.

Chondromodulin is necessary for cartilage callus distraction in mice.

Chondromodulin (Cnmd) is a glycoprotein known to stimulate chondrocyte growth. We examined in this study the expression and functional role of Cnmd during distraction osteogenesis that is modulated by mechanical forces. The right tibiae of the mice were separated by osteotomy and subjected to slow progressive distraction using an external fixator. In situ hybridization and immunohistochemical analyses of the lengthened segment revealed that Cnmd mRNA and its protein in wild-type mice were localized in the cartilage callus, which was initially generated in the lag phase and was lengthened gradually during the distraction phase. In Cnmd null (Cnmd-/-) mice, less cartilage callus was observed, and the distraction gap was filled by fibrous tissues. Additionally, radiological and histological investigations demonstrated delayed bone consolidation and remodeling of the lengthened segment in Cnmd-/- mice. Eventually, Cnmd deficiency caused a one-week delay in the peak expression of VEGF, MMP2, and MMP9 genes and the subsequent angiogenesis and osteoclastogenesis. We conclude that Cnmd is necessary for cartilage callus distraction.

Novel nano-hydroxyapatite coating of additively manufactured three-dimensional porous implants improves bone ingrowth and initial fixation.

Electron beam melting (EBM) has been used to fabricate three-dimensional (3D) porous Ti-6Al-4V surfaces for acetabular cups in total hip arthroplasty. However, there are radiographic concerns regarding poor implant fixation and bone ingrowth around electron beam melted (EBMed) 3D porous cups. We hypothesize that nano-hydroxyapatite (nHA) coating can promote bone ingrowth and thus decrease the occurrence of radiolucent lines around EBMed 3D porous cups. This study aimed to investigate the effect of a novel nHA coating on the biological performance of EBMed 3D porous implants in a beagle transcortical model. Low-porosity (control) and high-porosity 3D porous Ti-6Al-4V implants were manufactured using EBM. Half of the high-porosity implants were coated with nHA without clogging the 3D pores. Implants were inserted into the femoral diaphysis of the beagles. The beagles were euthanized at 4, 8, and 12 weeks postoperatively, and push-out testing was performed. Bone ingrowth was evaluated by histological analysis. Although the increase in porosity alone had no effect on biological behavior, the addition of nHA to high-porosity 3D implants significantly improved early bone fixation and bone ingrowth into the deep region of porous structures compared to low-porosity implants. This is the first report of a novel nHA coating that improved bone ingrowth into the deeper regions of 3D porous implants, which can prevent the occurrence of radiolucent lines around EBMed 3D porous cups.

Reference intervals and sources of variation of pressure pain threshold for quantitative sensory testing in a Japanese population.

Quantitative sensory testing (QST) is useful when analysing musculoskeletal pain disorders. A handheld algometer is most commonly used for pressure pain threshold (PPT) tests. However, reference intervals for PPTs are not elucidated. We assessed reference intervals of PPTs for QST in 158 healthy adult Japanese with no history of musculoskeletal or neurological problems. A handheld algometer was used to record PPT at five different assessment sites on the body: lumbar paravertebral muscle, musculus gluteus maximus, quadriceps, tibialis anterior muscle, and anterior talofibular ligament. Multiple regression analysis was performed to explore sources of variation of PPT according to sex, age, body mass index, UCLA Activity Level Rating, and Tegner Activity Score. Reference intervals were determined parametrically by Gaussian transformation of PPT values using the two-parameter Box-Cox formula. Results of multiple regression analysis revealed that age was significantly associated with PPT of lumbar paravertebral muscle and musculus gluteus maximus. In females, body mass index showed significant positive correlation with PPT of anterior talofibular ligament, and UCLA Activity Level Rating also showed significant positive association with tibialis anterior muscle and anterior talofibular ligament. Site-specific reference intervals of PPTs for Japanese are of practical relevance in fields of pain research using a handheld algometer.

Aryl hydrocarbon receptor-mediated impairment of chondrogenesis and fracture healing by cigarette smoke and benzo(a)pyrene.

The clinical literature strongly suggests that bone healing in cigarette smokers is impaired. Since cigarette smoke (CS) contains numerous polycyclic aromatic hydrocarbons (PAHs), and since dioxins impair bone formation in vivo via the Aryl Hydrocarbon Receptor (AHR), we investigated the impact of PAH/AHR signaling on chondrogenesis and on healing in a mouse tibial fracture model. We established that CS activates AHR signaling in fractures by up-regulating the AHR target gene cytochrome p4501A1 (Cyp1A1). For in vitro studies, we employed the mouse limb bud micromass chondrogenesis model. After confirming that chondrocytes express AHR during differentiation, we treated cells with a prototypical PAH found in CS, benzo(a)pyrene (BaP), or cigarette smoke extract (CSE). Both BaP and CSE strongly inhibited chondrogenesis in mesenchymal cells generated from E11 limb buds, with BaP also accelerating chondrocyte hypertrophy in cultures generated from E12 limb buds. Detection of DNA adducts in the BaP-treated cultures suggests that the distinct phenotypic effects of BaP may be due to the formation of reactive metabolites. Blockade of AHR signaling with the AHR antagonist MNF reverses the effects of BaP, but not CSE, suggesting that CSE inhibition of chondrogenesis is AHR-independent. Correlating with these results, tibial fracture calluses from BaP-treated mice were smaller and contained less mineralized tissue than vehicle controls. Overall, BaP is identified as a potent inhibitor of chondrogenesis in vitro with correlated effects on fracture healing similar to those of CS itself, suggesting a basis for PAHs as key compounds in the influence of CS on fracture repair.

Optimal intraoperative medial joint gap in extension to prevent flexion contracture following total knee arthroplasty using modified gap balancing technique.

Background: Primary aim to identify the ideal medial joint gap in extension needed to prevent post-operative flexion contracture following total knee arthroplasty (TKA) in varus osteoarthritic knees by the modified gap balancing technique. A secondary aim was to analyze multiple factors that influence knee extension in TKA by modified gap balancing. Methods: This is a prospective cohort study of 150 patients diagnosed with osteoarthritic varus knee who underwent TKA using the modified gap balancing technique. Operative and clinical records were assessed to determine factors including age, BMI (Body mass index), pre-operative extension angle and the medial extension laxity. Patients were followed for 6-months post-operatively and reviewed for knee extension angle. Results: Six months final follow-up information was available for 148 patients with an average age of 75.5 years. Pre-operative knee extension and BMI were significantly associated with post-operative knee extension. Post-operative flexion contracture of ≧ 100 was not seen in any of 34 patients with a medial extension laxity ≧ 0 mm who had no pre-existing flexion contracture, and in 1/9 (11.1%) patients with a medial extension laxity ≧ 1 mm who had pre-existing flexion contracture. Conclusions: Pre-operative extension angle and BMI significantly influence the post-operative knee extension angle in TKA using the modified gap balancing technique. A medial extension laxity of at least 1 mm is ideally needed to prevent post-operative flexion contracture in patients with a pre-existing contracture ≧ 100. Level of evidence: Level II; Prospective cohort study.

Resurfacing Egg-shell Patellar Defect in a Single-staged Primary total Knee Arthroplasty - A Case Report.

Introduction: Patellofemoral biomechanics are a very critical factor for patient satisfaction after total knee arthroplasty. Patellar defects in a primary total knee arthroplasty are rare. We present a rare case of valgus deformed knee with an eroded egg-shell like patella managed with primary knee arthroplasty. Case Report: A 58-year-old female with bilateral knee pain for 35-years presented to us with a bilateral valgus knee. The knee range of movement was restricted more on the left side and severely restricting her activities of daily living. She had an egg-shell like eroded patellar defect in an osteoarthritic knee for which, she underwent primary total knee arthroplasty and patellar resurfacing with autologous bone graft harvested from the tibial cut bone. Conclusion: We have presented a rare case of a combination of patellar defect in an Osteoarthritic knee which was managed by modified gapbalancing technique of TKA with a novel method of patellar resurfacing in a single stage with good functional results at 1-year postoperatively. This case improves our understanding of the management of such complex scenarios and, more importantly raises the questions our understanding and need of classification of such patellar defects in a primary arthritic knee.

Current Concept of Quantitative Sensory Testing and Pressure Pain Threshold in Neck/Shoulder and Low Back Pain.

In recent years, several published articles have shown that quantitative sensory testing (QST) and pressure pain threshold (PPT) are useful in the analysis of neck/shoulder and low back pain. A valid reference for normal PPT values might be helpful for the clinical diagnosis of abnormal tenderness or muscle pain. However, there have been no reliable references for PPT values of neck/shoulder and back pain because the data vary depending on the devices used, the measurement units, and the area examined. In this article, we review previously published PPT articles on neck/shoulder and low back pain, discuss the measurement properties of PPT, and summarize the current data on PPT values in patients with chronic pain and healthy volunteers. We also reveal previous issues related to PPT evaluation and discuss the future of PPT assessment for widespread use in general clinics. We outline QST and PPT measurements and what kinds of perceptions can be quantified with the PPT. Ninety-seven articles were selected in the present review, in which we focused on the normative values and abnormal values in volunteers/patients with neck/shoulder and low back pain. We conducted our search of articles using PubMed and Medline, a medical database. We used a combination of "Pressure pain threshold" and "Neck shoulder pain" or "Back pain" as search terms and searched articles from 1 January 2000 to 1 June 2022. From the data extracted, we revealed the PPT values in healthy control subjects and patients with neck/shoulder and low back pain. This database could serve as a benchmark for future research with pressure algometers for the wide use of PPT assessment in clinics.

Overexpressed osteoactivin reduced osteoclastic callus resorption during distraction osteogenesis in mice.

Distraction osteogenesis is a widely used surgical technique to treat bone deformity and shortening. Several biological treatments have been studied to enhance bone formation during distraction osteogenesis in animals. However, role of osteoactivin in the osseous tissues during distraction osteogenesis remains poorly understood. In this animal experimental study, we investigated the spatiotemporal expression of osteoactivin by immunohistochemistry and real-time PCR using a mouse model for tibial lengthening. Furthermore, to address the role of osteoactivin in bone lengthening, we subjected the osteoactivin-transgenic mice to distraction osteogenesis model. During the lag phase, the fibroblast-like cells (possible progenitors of the osteoblasts or chondrocytes), which mainly express osteoactivin, were infiltrated into the osteotomy site. Osteoactivin was ubiquitously expressed in the lengthened segment during the distraction and consolidation phases. Consistent with the immunohistochemical analysis, the levels of the osteoactivin transcripts in the tibias were significantly increased throughout the distraction osteogenesis process. The bone mineral content in the osteoactivin-transgenic mice calculated using peripheral quantitative computed tomography was also significantly increased at the remodeling zone. The histomorphometric analysis revealed that newly formed callus resorption in the remodeling zone was significantly reduced but bone formation was not altered in the osteoactivin-transgenic mice. We conclude that osteoactivin functions as an inhibitor of callus resorption during the consolidation phase of distraction osteogenesis.

Bisphosphonate-related atypical insufficiency fracture of the tibial plateau†:†A case report.

Objective : Only a few cases of insufficiency fractures of the tibial plateau following bisphosphonate use have been reported. The authors report a case with bisphosphonate (BP) -related atypical insufficiency fracture of tibial plateau, which developed delayed union. Patient : A 65-year-old Japanese woman presented with left knee pain without any trauma. She had a 5-year history of risedronate use for primary osteoporosis. Initial X-rays were unremarkable, but magnetic resonance imaging (MRI) confirmed an insufficiency fracture at the left tibial plateau at 3 weeks after the initial visit. Risedronate treatment was stopped because we diagnosed her with a BP-related atypical insufficiency fracture of the tibial plateau. She was treated with rest, a lateral wedge insole and protective weight-bearing with a T-cane for 3 months. Result : At 3-month follow-up, the patient still had a pain and a delayed healing on radiographs. Six months later, X-rays showed that the fracture site had a sclerotic change, but MRI revealed delayed union. At 8-month follow-up, the fracture was healed without any symptoms. Conclusion : All clinicians need to be aware of the delayed healing of atypical insufficiency fracture related with prolonged BP use. J. Med. Invest. 68 : 186-188, February, 2021.

Greater Trochanteric Fracture with Lesser Trochanter Extension: A Report of 2 Cases and CT-Based Finite Element Analysis.

CASE: Two patients (aged 71 and 82 years) presented with a greater trochanteric fracture with lesser trochanter extension. These cases were successfully treated by prophylactic osteosynthesis to prevent secondary intertrochanteric/cervical fracture and to facilitate an early return to daily life. We also clarified the mechanical strength of the area that escaped bone fracture using the patient-specific computed tomography-based finite element method (CT/FEM). CONCLUSIONS: The present fractured femurs were shown to halve the axial compression strength and had only one-sixth torsional strength in patient-specific CT/FEM. These data support prophylactic surgery to prevent the secondary fractures because of this injury.

Significant reduction of patellar height affected lower clinical outcomes and knee flexion over five-year follow-up after total knee arthroplasty.

AIMS: This study aimed to investigate the relationship between changes in patellar height and clinical outcomes at a mean follow-up of 7.7 years (5 to 10) after fixed-bearing posterior-stabilized total knee arthroplasty (PS-TKA). METHODS: We retrospectively evaluated knee radiographs of 165 knees, which underwent fixed-bearing PS-TKA with patella resurfacing. The incidence of patella baja and changes in patellar height over a minimum of five years of follow-up were determined using Insall-Salvati ratio (ISR) measurement. We examined whether patella baja (ISR < 0.8) at final follow-up affected clinical outcomes, knee joint range of motion (ROM), and Knee Society Score (KSS). We also assessed inter- and intrarater reliability of ISR measurements and focused on the relationship between patellar height reduction beyond measurement error and clinical outcomes. RESULTS: The ISR gradually decreased over five years after TKA, and finally 33 patients (20.0%) had patella baja. Patella baja at the final follow-up was not related to passive knee ROM or KSS. Interestingly, when we divided into two groups - patella baja and patella normal-alta (ISR ≥ 0.8) - the patella baja group already had a lower patellar height before surgery, compared with the patella normal-alta group. The ISR measurement error in this study was 0.17. Both passive knee flexion and KSS were significantly decreased in the group with a decrease in ISR of ≥ 0.17 at final follow-up. CONCLUSION: Patellar height gradually decreased over five years of follow-up after TKA. The reduction in patellar height beyond measurement error following TKA was associated with lower clinical outcomes. Cite this article: Bone Jt Open 2021;2(12):1075-1081.

Effects of sclerostin antibody on bone healing.

Promoting bone healing after a fracture has been a frequent subject of research. Recently, sclerostin antibody (Scl-Ab) has been introduced as a new anabolic agent for the treatment of osteoporosis. Scl-Ab activates the canonical Wnt (cWnt)-ß-catenin pathway, leading to an increase in bone formation and decrease in bone resorption. Because of its rich osteogenic effects, preclinically, Scl-Ab has shown positive effects on bone healing in rodent models; researchers have reported an increase in bone mass, mechanical strength, histological bone formation, total mineralized callus volume, bone mineral density, neovascularization, proliferating cell nuclear antigen score, and bone morphogenic protein expression at the fracture site after Scl-Ab administration. In addition, in a rat critical-size femoral-defect model, the Scl-Ab-treated group demonstrated a higher bone healing rate. On the other hand, two clinical reports have researched Scl-Ab in bone healing and failed to show positive effects in the femur and tibia. This review discusses why Scl-Ab appears to be effective in animal models of fracture healing and not in clinical cases.

The AO trauma CPP bone infection registry: Epidemiology and outcomes of Staphylococcus aureus bone infection.

Bone infection represents a serious complication of orthopedic surgery and Staphylococcus aureus is the most common pathogen. To improve the understanding of host-pathogen interaction, we developed a biospecimen registry (AO Trauma CPP Bone Infection Registry) to collect clinical data, bacterial isolates, and serum from patients with S. aureus bone infection. A prospective multinational registry with a 12-month follow-up was created to include adult patients (18 years or older) with culture-confirmed S. aureus infection in long bones after fracture fixation or arthroplasty. Baseline patient attributes and details on infections and treatments were recorded. Blood and serum samples were obtained at baseline, 6, and 12 months. Patient-reported outcomes were collected at 1, 6, and 12 months. Clinical outcomes were recorded. Two hundred and ninety-two patients with fracture-related infection (n = 157, 53.8%), prosthetic joint infection (n = 86, 29.5%), and osteomyelitis (n = 49, 16.8%) were enrolled. Methicillin-resistant S. aureus was detected in 82 patients (28.4%), with the highest proportion found among patients from North American sites (n = 39, 48.8%) and the lowest from Central European sites (n = 18, 12.2%). Patient outcomes improved at 6 and 12 months in comparison to baseline. The SF-36 physical component summary mean (95% confidence interval) score, however, did not reach 50 at 12 months. The cure rate at the end of the study period was 62.1%. Although patients improved with treatment, less than two-thirds were cured in 1 year. At 12-month follow-up, patient-reported outcome scores were worse for patients with methicillin-resistant S. aureus infections.