Scott R. Montgomery

Analysis of Rotator Cuff Repair Trends in a Large Private Insurance Population

PURPOSE The purpose of this study was to identify current trends in open and arthroscopic surgical treatment of rotator cuff tears across sex, age, and region in the United States. METHODS Using the PearlDiver Patient Record Database (PearlDiver, Fort Wayne, IN), a publicly available national database of insurance records, patients who underwent rotator cuff repair from 2004 through 2009 were identified. The number of open (CPT codes 23410, 23412, 23420) and arthroscopic (CPT code 29827) rotator cuff repairs were quantified in isolation and in combination with acromioplasty (CPT codes 23415, 29826). The type of procedure, date, sex, and region of the country was identified for each patient. Trend tests (χ(2) and Cochran-Armitage) were used to determine statistical significance. RESULTS There were 151,866 rotator cuff repair procedures identified in the database from 2004 through 2009, which represented an incidence of 13.6 for every 1,000 patients assigned an orthopaedic International Classification of Diseases, Ninth Revision (ICD-9) or Current Procedural Terminology (CPT) code. Male patients accounted for 60% of the repairs and female patients for 40%. There were 98,174 arthroscopic cuff repairs (65%) and 53,692 open repairs (35%). The annual percentage of arthroscopic cases increased from 48.8% in 2004 to 74.3% in 2009, whereas the percentage of open cases decreased from 51.2% in 2004 to 25.7% in 2009 (P < .0001). Acromioplasty was also performed in 47.3% of cases, and the rate showed only a slight increase (from 46.6% to 47.8%) between 2004 and 2009 (P < .01). All regions of the United States showed similar surgical trends and trends for sex and age distributions. CONCLUSIONS Our analysis shows that the majority of rotator cuff repairs in the United States are now performed arthroscopically (>74%) and there has been a recent steady decline in performance of open rotator cuff repair. Concomitant acromioplasty is performed approximately half the time, and this trend is increasing slightly. These findings were consistent across age, sex, and region in the United States. LEVEL OF EVIDENCE IV, cross-sectional study.

Comparison of practice patterns in total ankle replacement and ankle fusion in the United States.

Background: Although tibiotalar fusion has historically been considered the gold standard treatment for end-stage arthritis of the ankle, the performance of total ankle replacement appears to be gaining favor as improved outcomes have been observed with new implant designs and surgical techniques. The purpose of this study was to compare trends and demographics in the performance of ankle fusion and total ankle replacement in the United States. Methods: The Current Procedural Terminology (CPT) codes of patients undergoing ankle fusion and total ankle replacement were searched using the PearlDiver Patient Record Database, a national database of orthopaedic patients. The CPT codes for open ankle arthrodesis (27870), arthroscopic ankle arthrodesis (29899), and total ankle replacement (27700, 27702) were searched for the years 2004 to 2009 to identify relative changes in the performance of ankle fusion and replacement over time. Results: The performance of ankle fusion was unchanged during the 6-year study period. In contrast, an increase in total ankle replacement was observed, from 0.63 cases per 10 000 patients searched in 2004 to 0.99 cases per 10 000 patients in 2009 (P < .05). Both ankle fusion and total ankle replacement were performed most commonly in patients aged 60 to 69 years (P < .05). Although an even gender distribution was observed in patients undergoing total ankle replacement, open and arthroscopic fusion were more commonly performed in males (P < .05). With regard to regional distribution, open and arthroscopic fusion were most commonly performed in the western region of the United States, whereas total ankle replacement was performed most frequently in the Midwest (P < .001). Conclusions: In the population studied, the performance of total ankle replacement increased 57% from 2004 to 2009 and was performed equally in male and female patients when compared to ankle fusion, which was more often performed in males and was unchanged with time. Level of Evidence: Level IV, cross-sectional study.

Biologic augmentation of rotator cuff repair

Rotator cuff repair is a common orthopedic procedure. Despite advances in surgical technique, the rotator cuff tendons often fail to heal after surgery. In recent years, a number of biologic strategies have been developed and tested to augment healing after rotator cuff repair. These strategies include allograft, extracellular matrices (ECMs), platelet rich plasma (PRP), growth factors, stem cells, and gene therapy. This chapter reviews the most current research on biologic augmentation of rotator cuff repair using these methods.

Cross-sectional Analysis of Trends in Meniscectomy and Meniscus Repair

Knee arthroscopy to address meniscus tears is among the most common orthopedic procedures performed, and technical advances in the treatment of meniscus tears have affected the treatment options available to orthopedic surgeons. The purpose of this study was to perform a large cross-sectional analysis of orthopedic patients to investigate trends in arthroscopic meniscectomy and meniscus repair in the United States. Patients who underwent arthroscopic meniscectomy (Current Procedural Terminology codes 29881 and 29880) and arthroscopic meniscus repair (Current Procedural Terminology codes 29882 and 29883) were identified using the PearlDiver Patient Record Database, which is a national database of insurance records. The authors identified 187,607 arthroscopic medial or lateral meniscectomies and repairs performed between 2004 and 2009. Ninety-six percent of patients underwent meniscectomy and 4% underwent repair. No change occurred in the incidence of medial or lateral meniscectomy. The incidence of medial meniscus repair decreased from 5.3 cases per 10,000 patients in 2004 to 3.8 in 2009 (P<.001), although no significant change occurred in the incidence of lateral meniscus repair. Medial meniscectomy was most commonly performed in patients aged 50 to 59 years, whereas lateral meniscectomy demonstrated a bimodal age distribution. Conversely, meniscus repairs were most frequently performed in patients aged 10 to 19 years. Sex differences were more pronounced with meniscus repair (63% male vs 37% female) compared with meniscectomy (53% male vs 47% female). A high frequency of meniscus debridement can be expected in arthroscopic knee surgery. Despite advances in meniscus repair techniques and devices, no increase occurred in the performance of meniscus repair compared with meniscectomy.

Surgical management of PCL injuries: indications, techniques, and outcomes

The ideal treatment for posterior cruciate ligament (PCL) injuries is controversial and remains an active area of orthopedic research. The indications for surgery and the ideal method of reconstruction continue to be evaluated in biomechanical and clinical studies. Recent research has provided information on the anatomy and biomechanics of the PCL, and the merits and drawbacks of the transtibial compared with the tibial inlay technique, the use of single vs double-bundle reconstruction, and different graft options for reconstruction. This review discusses important factors in the surgical treatment of PCL injuries, with attention to the most current literature on these topics.

A Novel Osteogenic Oxysterol Compound for Therapeutic Development to Promote Bone Growth: Activation of Hedgehog Signaling and Osteogenesis through Smoothened Binding

Osteogenic factors are often used in orthopedics to promote bone growth, improve fracture healing, and induce spine fusion. Osteogenic oxysterols are naturally occurring molecules that were shown to induce osteogenic differentiation in vitro and promote spine fusion in vivo. The purpose of this study was to identify an osteogenic oxysterol more suitable for clinical development than those previously reported, and evaluate its ability to promote osteogenesis in vitro and spine fusion in rats in vivo. Among more than 100 oxysterol analogues synthesized, Oxy133 induced significant expression of osteogenic markers Runx2, osterix (OSX), alkaline phosphatase (ALP), bone sialoprotein (BSP), and osteocalcin (OCN) in C3H10T1/2 mouse embryonic fibroblasts and in M2‐10B4 mouse marrow stromal cells. Oxy133‐induced activation of an 8X‐Gli luciferase reporter, its direct binding to Smoothened, and the inhibition of Oxy133‐induced osteogenic effects by the Hedgehog (Hh) pathway inhibitor, cyclopamine, demonstrated the role of Hh pathway in mediating osteogenic responses to Oxy133. Oxy133 did not stimulate osteogenesis via BMP or Wnt signaling. Oxy133 induced the expression of OSX, BSP, and OCN, and stimulated robust mineralization in primary human mesenchymal stem cells. In vivo, bilateral spine fusion occurred through endochondral ossification and was observed in animals treated with Oxy133 at the fusion site on X‐ray after 4 weeks and confirmed with manual assessment, micro‐CT (µCT), and histology after 8 weeks, with equal efficiency to recombinant human bone morphogenetic protein‐2 (rhBMP‐2). Unlike rhBMP‐2, Oxy133 did not induce adipogenesis in the fusion mass and resulted in denser bone evidenced by greater bone volume/tissue volume (BV/TV) ratio and smaller trabecular separation. Findings here suggest that Oxy133 has significant potential as an osteogenic molecule with greater ease of synthesis and improved time to fusion compared to previously studied oxysterols. Small molecule osteogenic oxysterols may serve as the next generation of bone anabolic agents for therapeutic development.

Prevalence and motion characteristics of degenerative cervical spondylolisthesis in the symptomatic adult.

Study Design. Retrospective analysis of kinetic magnetic resonance images. Objective. To define the prevalence of degenerative cervical spondylolisthesis in symptomatic patients and to analyze the motion characteristics and influence on the spinal canal at the affected level. Summary of Background Data. When compared with lumbar spondylolisthesis, there are few studies evaluating cervical spondylolisthesis, and the prevalence and motion characteristics of cervical spondylolisthesis are not well defined. Methods. Four hundred sixty-eight symptomatic patients underwent upright cervical kinetic magnetic resonance images in neutral, flexion, and extension positions. Segmental displacement and intervertebral angles were measured in 3 positions using computer analysis software. Spondylolisthesis was defined as the vertebral displacement more than 2 mm, and graded based on the magnitude into 2 groups at each level: grade 1 (2–3 mm), grade 2 (>3 mm). Instability was defined as segmental translational motion exceeding 3 mm. Results. Grade 1 and 2 spondylolisthesis at a minimum of 1 level were observed with a prevalence of 16.4% and 3.4% of all patients, respectively. The most affected levels were C4–C5 (6.2%) and C5–C6 (6.0%) followed by C3–C4 (3.6%) and C6–C7 (3.0%). Translational motion was greater in levels with grade 1 as compared with segments without spondylolisthesis, but there was no difference in angular motion between the 3 groups. Translational instability was observed with a prevalence of 16.7% in grade 2, 4.3% in grade 1, and 3.4% in segments without spondylolisthesis. Space available for the cord at the affected level was decreased and spinal cord compression grade was higher in grade 1 and grade 2 as compared with levels without spondylolisthesis. Conclusion. Cervical spondylolisthesis of at least 2 mm was observed in 20% of patients and was most common at C4–C5 and C5–C6. The presence of spondylolisthesis was associated with increased translational motion and decreased segmental spinal canal diameter. Level of Evidence: N/A

The Effect of Corticosteroid Administration on Soft-tissue Inflammation Associated With rhbmp-2 Use in a Rodent Model of Inflammation

Study Design. In vivo rodent model. Objective. Investigate the effect of systemic corticosteroid administration on soft-tissue inflammation after local delivery of recombinant human bone morphogenetic protein-2 (rhBMP-2). Summary of Background Data. Corticosteroid use in cases of soft-tissue inflammation associated with the use of rhBMP-2 has been reported in clinical studies, but the effectiveness of its use and appropriate timing remain unclear. Methods. Absorbable collagen sponges were implanted with control or rhBMP-2 into the lumbar region of rats subcutaneously and intramuscularly. Four groups were studied: group I, control sponge only; group 2, BMP-2 sponge only; group III, BMP-2 sponge and preoperative intraperitoneal methylprednisolone (MPSS); group IV, BMP-2 sponge with MPSS given on day 2. Using magnetic resonance imaging, inflammation was assessed in terms of soft tissue edema volume at 0, 2, 4, and 7 days. Rats were sacrificed after 7 days for gross and histological analysis. Results. The peak mean intramuscular inflammatory volume occurred on day 2 in all groups. Group II (BMP-2 without MPSS) had a significantly higher peak mean inflammatory volume (405.46 mm3) on day 2 than that of groups I (266 mm3), III (278 mm3), and IV (291 mm3) (P = 0.001). No significant difference in intramuscular soft-tissue inflammation was observed between the control group and the groups receiving MPSS on day 0 or day 2 at any time point. No differences in the area of inflammatory cell infiltrate surrounding the sponge was observed histologically, after sacrificing them, in groups treated with BMP-2. Conclusion. Systemic MPSS administration reduced soft tissue edema associated with rhBMP-2 as measured by magnetic resonance imaging, but no effect was observed on the histological area of inflammation. Further studies are required to elucidate if there is any benefit to the use of corticosteroid administration in reducing the area of inflammation associated with the use of rhBMP-2.

Failed rotator cuff surgery, evaluation and decision making.

Rotator cuff repair is very likely to be clinically successful when performed well and rehabilitated properly, especially when judged with patient satisfaction outcome scores. A healed rotator cuff tendon will likely result in an improved and lasting clinical result. Recurrent tears will still be present despite optimal mobilization and fixation of the rotator cuff to bone, especially in large tears with retraction and atrophy. Failure of rotator cuff repairs is multifactorial with biologic factors, such as age, tear size, and fatty infiltration probably most critical. Other patient-related factors (ie, diabetes, smoking), recurrent trauma, and technical error at the time of surgery also contribute to rotator cuff repair failure. When managing a patient with a symptomatic re-tear, revision rotator cuff repair can be a very successful procedure, but patient selection is critical and managing patient expectations is paramount. Ideal candidates for revision rotator cuff repair have minimal muscle atrophy, minimal tendon retracted, preoperative forward elevation of greater than 90°, a functioning deltoid, and no evidence of cuff tear arthropathy.

Secreted Phosphoprotein 24 kD (Spp24) and Spp14 Affect TGF-β Induced Bone Formation Differently

Transforming growth factor-β (TGF-β) and bone morphogenetic proteins (BMPs) have opposing but complementary functions in directing bone growth, repair, and turnover. Both are found in the bone matrix. Proteins that bind to and affect the activity of these growth factors will determine the relative abundance of the growth factors and, therefore, regulate bone formation. Secreted phosphoprotein 24 kD (Spp24) is a bone matrix protein that has been demonstrated to bind to and affect the activity of BMPs. The arginine-rich carboxy terminus of Spp24 is proteolytically processed to produce three other predictable truncation products (Spp18.1, Spp16.0, and Spp14.5). In this work, we report that kinetic data obtained by surface plasmon resonance demonstrate that Spp24 and the three C-terminal truncation products all bind to TGF-β1 and TGF-β2 with a similar but somewhat less affinity than they bind BMP-2; that, as in the case of BMP-2, the full-length (FL) form of Spp24 binds TGF-β with greater affinity than do the truncation products; that FL-Spp24 inhibits TGF-β2 induced bone formation in vivo, but Spp14.5 does not; and that co-administration of FL-Spp24 or Spp14.5 with TGF-β2 in vivo is associated with a reduction in the amount of cartilage, relative to new bone, present at the site of injection. This finding is consistent with the observation that low-dose TGF-β administration in vivo is associated with greater bone formation than high-dose TGF-β administration, and suggests that one function of Spp24 and its truncation products is to down-regulate local TGF-β activity or availability during bone growth and development. The similarities and differences of the interactions between Spp24 proteins and TGF-β compared to the interaction of the Spp24 proteins and BMPs have significant implications with respect to the regulation of bone metabolism and with respect to engineering therapeutic proteins for skeletal disorders.