Age-Dependent Electroencephalogram Features in Infants Under Spinal Anesthesia Appear to Mirror Physiologic Sleep in the Developing Brain: A Prospective Observational Study.

BACKGROUND: Infants under spinal anesthesia appear to be sedated despite the absence of systemic sedative medications. In this prospective observational study, we investigated the electroencephalogram (EEG) of infants under spinal anesthesia and hypothesized that we would observe EEG features similar to those seen during sleep. METHODS: We computed the EEG power spectra and spectrograms of 34 infants undergoing infraumbilical surgeries under spinal anesthesia (median age 11.5 weeks postmenstrual age, range 38-65 weeks postmenstrual age). Spectrograms were visually scored for episodes of EEG discontinuity or spindle activity. We characterized the relationship between EEG discontinuity or spindles and gestational age, postmenstrual age, or chronological age using logistic regression analyses. RESULTS: The predominant EEG patterns observed in infants under spinal anesthesia were slow oscillations, spindles, and EEG discontinuities. The presence of spindles, observed starting at about 49 weeks postmenstrual age, was best described by postmenstrual age ( P =.002) and was more likely with increasing postmenstrual age. The presence of EEG discontinuities, best described by gestational age ( P = .015), was more likely with decreasing gestational age. These age-related changes in the presence of spindles and EEG discontinuities in infants under spinal anesthesia generally corresponded to developmental changes in the sleep EEG. CONCLUSIONS: This work illustrates 2 separate key age-dependent transitions in EEG dynamics during infant spinal anesthesia that may reflect the maturation of underlying brain circuits: (1) diminishing discontinuities with increasing gestational age and (2) the appearance of spindles with increasing postmenstrual age. The similarity of these age-dependent transitions under spinal anesthesia with transitions in the developing brain during physiological sleep supports a sleep-related mechanism for the apparent sedation observed during infant spinal anesthesia.

Coccygectomy for refractory coccygodynia: a systematic review and meta-analysis.

PURPOSE: We sought to systematically assess and summarize the available literature on outcomes following coccygectomy for refractory coccygodynia. METHODS: PubMed, Scopus, and Cochrane Library databases were systematically searched in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Data concerning patient demographics, validated patient reported outcome measures (PROMs) for pain relief, disability outcomes, complications, and reoperation rates were extracted and analyzed. RESULTS: A total of 21 studies (18 retrospective and 3 prospective) were included in the quantitative analysis. A total of 826 patients (females = 75%) received coccygectomy (720 total and 106 partial) for refractory coccygodynia. Trauma was reported as the most common etiology of coccygodynia (56%; n = 375), followed by idiopathic causes (33%; n = 221). The pooled mean difference (MD) in pain scores from baseline on a 0-10 scale was 5.03 (95% confidence interval [CI]: 4.35 to 6.86) at a 6-12 month follow-up (FU); 5.02 (95% CI: 3.47 to 6.57) at > 12-36 months FU; and 5.41 (95% CI: 4.33 to 6.48) at > 36 months FU. The MCID threshold for pain relief was surpassed at each follow-up. Oswestry Disability Index scores significantly improved postoperatively, with a pooled MD from baseline of - 23.49 (95% CI: - 31.51 to - 15.46), surpassing the MCID threshold. The pooled incidence of complications following coccygectomy was 8% (95% CI: 5% to 12%), the most frequent of which were surgical site infections and wound dehiscence. The pooled incidence of reoperations was 3% (95% CI: 1% to 5%). CONCLUSION: Coccygectomy represents a viable treatment option in patients with refractory coccygodynia.

A case report of a distal radius fracture treated with a dorsal spanning plate augmented with fragment specific fixation.

Dorsal spanning plates are frequently utilized to manage comminuted intra-articular distal radius fractures, but there is little literature on combining them with augmented fixation in complex cases. We present a 43-year-old man who fell 5 ft onto his outstretched right hand. On examination, there was gross swelling and tenderness of the right wrist with no neurovascular deficit. Radiographs confirmed a comminuted intra-articular displaced distal radius fracture. He was treated with a dorsal spanning plate fixation combined with radiostyloid and volar buttress plates. Follow-up at 2 months showcased intact hardware with good fracture healing. The dorsal spanning plate was removed 4 months after the procedure with radiographs demonstrating adequate alignment and healing without failure. The patient reported no complaints and minimal functional disability. We highlight a case of augmenting a dorsal spanning plate with fragment-specific plate fixation for a comminuted intra-articular displaced distal radius fracture.

Awake Combined Spinal Caudal Anesthesia for Longer-Duration Urologic Surgery in Infants: A Case Series.

Awake combined spinal caudal anesthesia has been used as an anesthetic technique for longer-duration infraumbilical surgeries in infants. Literature on the safety and feasibility of this technique is limited. We share our experience with 27 infants undergoing longer-duration urologic surgery using awake combined spinal and caudal anesthesia without the use of systemic sedatives or inhalational agents. We describe our technique, safety considerations, and details surrounding the optimal timing of caudal catheter activation for prolongation of surgical anesthesia.

Combination radiofrequency ablation and vertebral cement augmentation for spinal metastatic tumors: A systematic review and meta-analysis of safety and treatment outcomes.

Background: The treatment of spine metastases continues to pose a significant clinical challenge, requiring the integration of multiple therapeutic modalities to address the multifactorial aspects of this disease process. Radiofrequency ablation (RFA) and vertebral cement augmentation (VCA) are 2 less invasive modalities compared to open surgery that have emerged as promising strategies, offering the potential for both pain relief and preservation of vertebral stability. The utility of these approaches, however, remains uncertain and subject to ongoing investigation.This systematic review and meta-analysis evaluates the available evidence and synthesize the results of studies that have investigated the combination of RFA and VCA for the treatment of spinal metastases, with the goal of providing a comprehensive and up-to-date assessment of the efficacy and safety of this therapeutic approach. Methods: A literature search was conducted using the electronic databases PubMed, Cochrane Central Register of Controlled Trials (CENTRAL), and Scopus from their inception to May 4th, 2022 in accordance with PRISMA guidelines. Studies were included if they met the following criteria: 1) spine metastases treated with RFA in combination with VCA, 2) available data on at least one outcome (i.e., pain palliation, complications, local tumor control), 3) prospective or retrospective studies with at least 10 patients, and 4) English language. Meta-analyses were conducted in R (R Foundation for Statistical Computing; Vienna, Austria), using the meta package. Results: In the 25 included studies, a total of 947 patients (females=53.9%) underwent RFA + VCA for spinal metastatic tumors. Out of 1,163 metastatic lesions, the majority were located in the lumbar region (585/1,163 [50.3%]) followed by thoracic (519/1,163 [44.6%]), sacrum (39/1,163 [3.4%]), and cervical (2/1,163 [0.2%]). 48/72 [66.7%] metastatic lesions expanded into the posterior elements. Preoperative pathologic vertebral fractures were identified in 115/176 [65.3%] patients. Between pre-procedure pain scores and postprocedure pain scores, average follow-up (FU) was 4.41±2.87 months. Pain scores improved significantly at a short-term FU (1-6 months), with a pooled mean difference (MD) from baseline of 4.82 (95% CI, 4.48-5.16). The overall local tumor progression (LTP) rate at short-term FU (1-6 months) was 5% (95% CI, 1%-8%), at mid-term FU (6-12 months) was 22% (95% CI, 0%-48%), and at long-term FU (>12 months) was 5% (95% CI, 0%-11%). The pooled incidence of total complications was 1% (95% CI, 0%-1%), the most frequent of which were transient radicular pain and asymptomatic cement extravasation. Conclusions: The findings of this meta-analysis reveal that the implementation of RFA in conjunction with VCA for the treatment of spinal metastatic tumors resulted in a significant short-term reduction of pain, with minimal total complications. The LTP rate was additionally low. The clinical efficacy and safety of this technique are established, although further exploration of the long-term outcomes of RFA+VCA is warranted.

Patient-reported hip pain and function are worse among elite Nordic ski athletes competing in ski jumping versus Nordic combined: a cross-sectional analysis.

OBJECTIVES: Nordic ski athletes are at increased risk of developing hip pain and dysfunction secondary to femoroacetabular impingement syndrome (FAIS), but it is unclear whether hip symptomatology differs between ski jumping (SJ) and Nordic combined (NC) athletes. The purpose of this study was to compare patient-reported hip pain and dysfunction between elite Nordic ski athletes participating in SJ versus NC. METHODS: A cross-sectional study was conducted involving SJ and NC athletes who competed at the international and U.S. national levels during the 2021-2022 season. Subjects were excluded if they had hip surgery within two years prior to enrollment. Subjects were asked to undergo diagnostic workups for FAIS, including physical examination and plain radiographic imaging. Subjects were asked to complete a survey that collected information on athletic and training history and to complete the hip disability and osteoarthritis outcome score (HOOS). Demographics, athletic/training history, and HOOS sub-scores were compared between the SJ and NC groups using the Student's t-test, Wilcoxon rank-sum test, or Fisher's exact test, as appropriate. p-values < 0.05 were considered significant. RESULTS: Twenty-four athletes (13 SJ, 11 NC) were included in the study. There were no statistically significant differences in age, sex, BMI, or age of menarche between the two groups (all p â€‹> â€‹0.05). There were also no statistically significant differences in the number of prior sports participated in, total hours of participation in prior sports, or total hours of training in Nordic specialization (all p â€‹> â€‹0.05). Among the 18 athletes who underwent physical examination (9 SJ, 9 NC), there were no statistically significant inter-group differences in hip range of motion or incidence of positive impingement tests (all p â€‹> â€‹0.05). Among the 19 athletes who underwent imaging (9 SJ, 10 NC), there were no statistically significant inter-group differences in the incidence of cam or pincer morphology in at least one hip (all p â€‹> â€‹0.05). SJ athletes had statistically significantly worse HOOS sub-scores for hip symptoms and stiffness, hip function in sports/recreational activities, and hip-related quality of life compared to NC athletes (all p â€‹< â€‹0.05). CONCLUSION: Elite SJ athletes have worse self-reported hip function compared to elite NC athletes, despite comparable demographics, athletic history, and duration of ski training. LEVEL OF EVIDENCE: IV.

Intradural Extramedullary Spinal Metastases from Non-neurogenic Primary Tumors: A Systematic Review.

BACKGROUND/AIM: Intradural extramedullary spinal metastases (IESMs) may severely affect quality-of-life of oncological patients. Several treatments are available but their impact on prognosis is unclear. We systematically reviewed the literature on IESMs of non-neurogenic origin. MATERIALS AND METHODS: PubMed, Ovid EMBASE, Scopus, and Web-of-Science were screened to include articles reporting patients with IESMs from non-neurogenic primary tumors. Clinico-radiological presentation, treatments, and outcomes were analyzed. RESULTS: We included 51 articles encompassing 130 patients of a median age of 62 years (range=32-91 years). The most common primary neoplasms were pulmonary (26.2%), renal (20%), and breast (13.8%) carcinomas. Median time interval from primary tumor to IESMs was 18 months (range=0-240 months). The most common symptoms were sensory (58.3%) and motor (54.2%) deficits. Acute cauda equina syndrome was reported in 29 patients (37.7%). Lesions were diagnosed at magnetic resonance imaging (93.3%), myelography (25%), or computed tomography (16.7%). All patients underwent decompressive laminectomy with tumor resection, partial (54.6%) more frequently than complete (43.1%). Adjuvant radiation (67.5%) and/or systemic (13.3%) therapies were administered. After treatment, most patients had symptom improvement (70.8%) and optimal radiological response (64.2%). Four patients experienced IESMs recurrences (3.1%) with median local tumor control of 14.5 months (range=0.1-36 months). Deaths occurred in 50% of patients, with median overall survival of 6.7 months (range=0.1-108 months). CONCLUSION: Patients with IESMs have significant tumor burden with poor prognoses. Resection and locoregional radiation may offer favorable clinico-radiological responses but are limited in achieving optimal local control and survival.

Radiofrequency ablation for spinal osteoid osteoma: A systematic review of safety and treatment outcomes.

AIM: We sought to systematically assess and summarize the available literature on the clinical outcomes and complications following radiofrequency ablation (RFA) for painful spinal osteoid osteoma (OO). METHODS: PubMed, Scopus, and CENTRAL databases were searched in accordance with PRISMA guidelines. Studies with available data on safety and clinical outcomes following RFA for spinal OO were included. RESULTS: In the 14 included studies (11 retrospective; 3 prospective), 354 patients underwent RFA for spinal OO. The mean ages ranged from 16.4 to 28 years (Females = 31.3%). Lesion diameters ranged between 3 and 20 mm and were frequently seen in the posterior elements in 211/331 (64%) patients. The mean distance between OO lesions and neural elements ranged between 1.7 and 7.4 mm. The estimated pain reduction on the numerical rating scale was 6.85/10 (95% confidence intervals [95%CI] 4.67-9.04) at a 12-24-month follow-up; and 7.29/10 (95% CI 6.67-7.91) at a >24-month follow-up (range 24-55 months). Protective measures (e.g., epidural air insufflation or neuroprotective sterile water infusion) were used in 43/354 (12.1%) patients. Local tumor progression was seen in 23/354 (6.5%) patients who were then successfully re-treated with RFA or open surgical resection. Grade I-II complications such as temporary limb paresthesia and wound dehiscence were reported in 4/354 (1.1%) patients. No Grade III-V complications were reported. CONCLUSION: RFA demonstrated safety and clinical efficacy in most patients harboring painful spinal OO lesions. However, further prospective studies evaluating these outcomes are warranted.

Evaluating the Optimal Management of Inoperable Giant Cell Tumors of the Spine: A Systematic Review and Meta-Analysis.

BACKGROUND: Surgical resection remains the preferred treatment in spine giant cell tumors (SGCTs), but it is not always feasible. Conservative strategies have been studied for inoperable cases. We systematically reviewed the literature on inoperable SGCTs treated with denosumab, radiotherapy or selective arterial embolization (SAE). METHODS: PubMed, Scopus, Web-of-Science, Ovid-EMBASE, and Cochrane were searched following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines to include studies of inoperable SGCTs treated with denosumab, radiotherapy or SAE. Treatment outcomes were analyzed and compared with a random-effect model meta-analysis. RESULTS: Among the 17 studies included, 128 patients received denosumab, 59 radiotherapy, and 43 SAE. No significant differences in baseline patient characteristics were found between the three groups. All strategies were equally effective in providing symptom improvement (p = 0.187, I2 = 0%) and reduction in tumor volume (p = 0.738, I2 = 56.8%). Rates of treatment-related complications were low (denosumab: 12.5%; radiotherapy: 8.5%; SAE: 18.6%) and comparable (p = 0.311, I2 = 0%). Patients receiving denosumab had significantly lower rates of local tumor recurrence (10.9%) and distant metastases (0%) compared to patients receiving radiotherapy (30.5%; 8.5%) or SAE (35.6%; 7%) (p = 0.003, I2 = 32%; p = 0.002, I2 = 47%). Denosumab was also correlated with significantly higher overall survival rates at 18 months (99.2%) and 24 months (99.2%) compared to radiotherapy (91.5%; 89.6%) and SAE (92.5%; 89.4%) (p = 0.019, I2 = 8%; p = 0.004, I2 = 23%). Mortality was higher in patients receiving SAE (20.9%) or radiotherapy (13.6%) compared to denosumab (0.8%) (p < 0.001), but deaths mostly occurred for unrelated diseases. CONCLUSIONS: Denosumab, radiotherapy, and SAE are safe and effective for inoperable SGCTs. Clinical and radiological outcomes are mostly comparable, but denosumab may provide superior tumor control.

Arrestin-3 interaction with maternal embryonic leucine-zipper kinase.

Maternal embryonic leucine-zipper kinase (MELK) overexpression impacts survival and proliferation of multiple cancer types, most notably glioblastomas and breast cancer. This makes MELK an attractive molecular target for cancer therapy. Yet the molecular mechanisms underlying the involvement of MELK in tumorigenic processes are unknown. MELK participates in numerous protein-protein interactions that affect cell cycle, proliferation, apoptosis, and embryonic development. Here we used both in vitro and in-cell assays to identify a direct interaction between MELK and arrestin-3. A part of this interaction involves the MELK kinase domain, and we further show that the interaction between the MELK kinase domain and arrestin-3 decreases the number of cells in S-phase, as compared to cells expressing the MELK kinase domain alone. Thus, we describe a new mechanism of regulation of MELK function, which may contribute to the control of cell fate.

The effect of postoperative immobilization on the healing of radiofrequency heat probe modified tissue: assessment of tissue length, stiffness, and morphology.

The effect of postoperative immobilization on the length, stiffness, and structure of connective tissue after radiofrequency probe shrinkage was examined in a rabbit patellar tendon model. Tendon lengths were measured before, immediately following, and 2, 4, and 8 weeks following heat application, with the contralateral tendon as a control. The animals were randomly assigned to three groups. In Group I, the controls, the animals were allowed free caged activity for 8 weeks. In Groups II and III, the experimental limb was immobilized at 15 degrees of knee flexion for 2 and 4 weeks, respectively, after which the animals were allowed 6 and 4 weeks of free caged activity. Changes in tendon length, stiffness, and cross-sectional area were compared using repeated measures ANOVA and differences between groups examined using Tukey's post-hoc analysis. Patellar tendon lengths were increased in all 3 groups at 8 weeks (P< .001). Tissue elongation was less extensive in group III compared to group I at 8 weeks (P< .001), while tissue cross-sectional area was decreased in both groups II and III compared to group I at 8 weeks (P< .001). All groups demonstrated decreases in tensile strength when compared to controls (P< .001). These findings suggest that postoperative immobilization is important following thermal shrinkage of connective tissue, as early activity can lead to stretching of the heat-modified tissue.

Ponatinib Activates an Inflammatory Response in Endothelial Cells via ERK5 SUMOylation.

Ponatinib is a multi-targeted third generation tyrosine kinase inhibitor (TKI) used in the treatment of chronic myeloid leukemia (CML) patients harboring the Abelson (Abl)-breakpoint cluster region (Bcr) T315I mutation. In spite of having superb clinical efficacy, ponatinib triggers severe vascular adverse events (VAEs) that significantly limit its therapeutic potential. On vascular endothelial cells (ECs), ponatinib promotes EC dysfunction and apoptosis, and inhibits angiogenesis. Furthermore, ponatinib-mediated anti-angiogenic effect has been suggested to play a partial role in systemic and pulmonary hypertension via inhibition of vascular endothelial growth factor receptor 2 (VEGFR2). Even though ponatinib-associated VAEs are well documented, their etiology remains largely unknown, making it difficult to efficiently counteract treatment-related adversities. Therefore, a better understanding of the mechanisms by which ponatinib mediates VAEs is critical. In cultured human aortic ECs (HAECs) treated with ponatinib, we found an increase in nuclear factor NF-kB/p65 phosphorylation and NF-kB activity, inflammatory gene expression, cell permeability, and cell apoptosis. Mechanistically, ponatinib abolished extracellular signal-regulated kinase 5 (ERK5) transcriptional activity even under activation by its upstream kinase mitogen-activated protein kinase kinase 5α (CA-MEK5α). Ponatinib also diminished expression of ERK5 responsive genes such as Krüppel-like Factor 2/4 (klf2/4) and eNOS. Because ERK5 SUMOylation counteracts its transcriptional activity, we examined the effect of ponatinib on ERK5 SUMOylation, and found that ERK5 SUMOylation is increased by ponatinib. We also found that ponatibib-mediated increased inflammatory gene expression and decreased anti-inflammatory gene expression were reversed when ERK5 SUMOylation was inhibited endogenously or exogenously. Overall, we propose a novel mechanism by which ponatinib up-regulates endothelial ERK5 SUMOylation and shifts ECs to an inflammatory phenotype, disrupting vascular homeostasis.

Determinants of patient satisfaction with outcome after shoulder arthroplasty.

The purpose of this investigation was to identify the determinants of patient satisfaction with outcome after hemiarthroplasty and total shoulder arthroplasty. Seventy patients who underwent shoulder arthroplasty were studied to determine predictors of patient satisfaction. Patient satisfaction was graded on an ordinal scale from 1 to 10. There was a significant association between patient satisfaction and age (P = .010) and between patient satisfaction and worker's compensation status (P = .018). There was no significant decrease in patient satisfaction for patients with rotator cuff tears. Patient satisfaction was significantly associated with all pain and function variables at follow-up (P < .05). The American Shoulder and Elbow Surgeons score was significantly correlated with patient satisfaction (P = 0.680, P < .05). Independent predictors of satisfaction included pain with activities of daily living, painless use of the arm above the shoulder, and difficulty with toileting (R(2) = 0.555). Subjective variables associated with pain were independent predictors of patient satisfaction. Thus, in assessing patient satisfaction after shoulder arthroplasty, we emphasize the importance of patient-derived subjective assessment of symptoms and function.

Differential responses to branched and unsaturated aliphatic hydrocarbons in the rat olfactory system.

In an effort to understand mammalian olfactory processing, we have been describing the responses to systematically different odorants in the glomerular layer of the main olfactory bulb of rats. Previously, we demonstrated chemotopically organized and distinct olfactory responses to a homologous series of straight-chained alkanes that consisted of purely hydrocarbon structures, indicating that hydrocarbon chains could serve as molecular features in the combinatorial coding of odorant information. To better understand the processing of hydrocarbon odorants, we now have examined responses to other types of chemical changes in these kinds of molecules, namely, branching and carbon-carbon bond saturation. To this end, we used the [14C]2-deoxyglucose method to determine glomerular responses to a group of eight-carbon branched alkane isomers, unsaturated octenes (double-bonded), and octynes (triple-bonded). In contrast to the differential responses we observed previously for straight-chained alkanes of differing carbon number, the rat olfactory system was not particularly sensitive to these variations in branching and bond saturation. This result was unexpected, given the distinct molecular conformations and property profiles of the odorants. The similarity in activity patterns was paralleled by a similarity in spontaneous perceptual responses measured using a habituation assay. These results demonstrate again the functional relationship between bulbar activity patterns and odor perception. The results further suggest that the olfactory system does not respond equally to all aspects of odorant chemistry, functioning as a specific, rather than a general, chemical analysis system.

Management of bone loss associated with recurrent anterior glenohumeral instability.

The diagnosis and treatment of osseous deficiencies associated with anterior shoulder instability have been a challenge to physicians for centuries. Whereas historical goals centered on the stable reduction and prevention of recurrent dislocation, current standards of success are predicated on the restoration of motion and strength and the return to functional activities, including competitive athletics. Reestablishment of anterior shoulder stability thus requires the recognition of osseous defects of the humeral head and glenoid, as well as a thorough understanding of the available treatment options in the context of a disciplined treatment algorithm. Although many surgical procedures have been described for the management of osseous deficiencies in association with anterior shoulder instability, in the authors' experience, such procedures are seldom necessary. The purpose of this summary is to review treatment options as well as indications and techniques to address these bony deficiencies.

Orthopaedic care of the aging athlete.

Increasing numbers of middle-aged and older adults participate in sports, and athletes wish to remain active as they age. Understanding the anatomic, physiologic, and psychosocial differences between older and younger athletes can help aging athletes maintain function. Athletic capacity may be sustained well into advanced age, and many of the physiologic consequences of aging may be mitigated or reversed by regular exercise. Most injuries in older athletes are chronic and overuse injuries that result in diminished flexibility and endurance. In addition, many aging athletes have medical and musculoskeletal problems that mandate tailoring athletic activity to the patient's general health and functional requirements.

Osteochondral lesions of the talus.

Osteochondral lesions of the talus occur infrequently and usually represent late sequelae of ankle trauma. Because of the functional significance of the talus and its limited capacity for repair, correct early diagnosis is important. Osteochondral fractures should be suspected in patients with chronic ankle pain, especially those with a prior ankle injury. Historically, plain radiographs have been used to stage lesions; more recently, magnetic resonance imaging and arthroscopy have been used. Non-surgical management remains the mainstay of treatment of acute, nondisplaced osteochondral lesions. Surgical management is reserved for unstable fragments or failure of nonsurgical treatment. Recent advances in osteochondral grafting have allowed reconstruction of the talar dome, leading to more predictable relief of pain and improvement of function.

Os acromiale: evaluation and treatment.

Os acromiale is a developmental aberration in which the distal acromion fails to fuse. This aberration is often discovered incidentally but may present with a clinical picture similar to that of subacromial impingement syndrome. Treatment for symptomatic os acromiale is initially nonoperative-activity modification, physical therapy, corticosteroid injection, use of nonsteroidal anti-inflammatory medication. Nonoperative management of clinically significant, radiographically confirmed os acromiale should be pursued for at least 6 months before consideration of surgical intervention. Subacromial decompression is often necessary to address symptoms of impingement. Excision of the os fragment may provide definitive treatment for smaller fragments (<3 cm). Removal of larger fragments remains controversial and should be approached with caution. Surgical fixation of larger fragments with or without supplemental autograft in conjunction with a structured postoperative program of physical therapy can reliably provide relief for symptomatic os acromiale.

Expression of bone morphogenetic proteins, receptors, and tissue inhibitors in human fetal, adult, and osteoarthritic articular cartilage.

Coordinate expression of BMPs and their receptors and inhibitors is likely necessary for physiologic BMP regulation and activity. To characterize the expression of such factors in fetal, normal adult, and end-stage osteoarthritic articular cartilage, samples from these sources were analyzed. PCR-amplified sequences (BMPs 1-11), receptors (IA, IB, II), TGF-beta1, TGF-beta2, inhibitors noggin and follistatin, CDMP-1, COMP, and GAPDH from cDNAs generated from extracted total RNA were resolved by gel electrophoresis. Protein levels of BMPs 3, 7, and 8 were also analyzed by SDS-PAGE and Western blotting. RT-PCR revealed that BMPs 1, 2, 4-6, and 11, BMPR-IA and II, noggin, follistatin, CDMP-1, COMP, and GAPDH mRNAs were expressed in similar fashion in both fetal and adult (normal or osteoarthritic) cartilage. BMPs 9 and 10 mRNAs were not expressed in either group. BMPs 7, 8, and BMPR-IB mRNAs were consistently expressed in fetal but not in adult cartilage. BMP-3 mRNA was expressed in fetal and normal adult, but not in osteoarthritic samples. TGF-beta1 was expressed in both adult normal and osteoarthritic, but not fetal, samples. Similarly, Western blotting demonstrated BMPs 7 and 8 to be present in fetal but not in adult samples. BMP-3 protein was present in fetal and adult normal samples, to a lesser extent, but absent in osteoarthritic cartilage.