The Jon Block Group

San Francisco, CA, United States

The Jon Block Group

San Francisco, CA, United States
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Yuan P.S.,UNITED ORTHOPEDIC GROUP | Rowshan K.,UNITED ORTHOPEDIC GROUP | Verma R.B.,University Orthopaedic Associates | Miller L.E.,Miller Scientific Consulting Inc. | And 2 more authors.
Journal of Orthopaedic Surgery and Research | Year: 2014

Background: Minimally invasive lateral approaches to the lumbar spine have been adopted to allow access to the intervertebral disc space while avoiding the complications associated with anterior or posterior approaches. This report describes a minimally invasive technique for lateral lumbar interbody fusion LLIF that allows direct intraoperative visualization of the psoas and surrounding neurovasculature (DV-LIF).Methods: The technique utilizes a radiolucent tubular retractor and a secondary psoas retractor that allows a muscle-sparing approach while offering excellent visualization of the operative site. The unique advantage of this procedure is that the psoas muscle and surrounding nerves can be directly visualized intraoperatively to supplement neuromonitoring. We retrospectively reviewed complication rates in 34 patients treated with DV-LLIF (n = 19) or standard lateral lumbar interbody fusion (S-LLIF, n = 15).Results: There were 29 complications (median: 1 per patient) with DV-LLIF and 20 (median: 1 per patient) complications with S-LLIF. Postoperative sensory deficits were reported in eight (42%) and seven (47%) patients, respectively. Thigh pain or numbness was reported in eight (42%) and five (33%) patients, respectively. The percentage of the overall complications directly attributable to the procedure was 69% with DV-LLIF and 83% with S-LLIF. One severe complication (back pain) was reported in one DV-LLIF patient and four severe complications (severe bleeding, respiratory failure, deep venous thrombosis and gastrointestinal prophylaxis, and nicked renal vein and aborted procedure) were reported in two S-LLIF patients.Conclusions: Preliminary evidence suggests that minimally invasive lateral interbody fusion with direct psoas visualization may reduce the risk for severe procedural complications. © 2014 Yuan et al.; licensee BioMed Central Ltd.


Zeilstra D.J.,Bergman Clinics | Miller L.E.,Miller Scientific Consulting Inc. | Miller L.E.,The Jon Block Group | Block J.E.,The Jon Block Group
Clinical Interventions in Aging | Year: 2013

Introduction: The aim of this study is to report our 6-year single-center experience with L5-S1 axial lumbar interbody fusion (AxiaLIF). Methods: A total of 131 patients with symptomatic degenerative disc disease refractory to nonsurgical treatment were treated with AxiaLIF at L5-S1, and were followed for a minimum of 1 year (mean: 21 months). Main outcomes included back and leg pain severity, Oswestry Disability Index score, working status, analgesic medication use, patient satisfaction, and complications. Computed tomography was used to determine postoperative fusion status. Results: No intraoperative complications, including vascular, neural, urologic, or bowel injuries, were reported. Back and leg pain severity decreased by 51% and 42%, respectively, during the follow-up period (both P< 0.001). Back function scores improved 50% compared to baseline. Clinical success, defined as improvement ≥30%, was 67% for back pain severity, 65% for leg pain severity, and 71% for back function. The employment rate increased from 47% before surgery to 64% at final follow-up (P<0.001). Less than one in four patients regularly used analgesic medications postsurgery. Patient satisfaction with the AxiaLIF procedure was 83%. The fusion rate was 87.8% at final follow-up. During follow-up, 17 (13.0%) patients underwent 18 reoperations on the lumbar spine, including pedicle screw fixation (n = 10), total disc replacement of an uninvolved level (n = 3), facet screw fixation (n = 3), facet screw removal (n = 1), and interbody fusion at L4-L5 (n = 1). Eight (6.1%) reoperations were at the index level. Conclusion: Single-level AxiaLIF is a safe and effective means to achieve lumbosacral fusion in patients with symptomatic degenerative disc disease. © 2013 Zeilstra et al. This work is published by Dove Medical Press Ltd.


London N.J.,Harrogate District Foundation Trust | Miller L.E.,Miller Scientific Consulting Inc. | Miller L.E.,The Jon Block Group | Block J.E.,The Jon Block Group
Clinical Medicine Insights: Arthritis and Musculoskeletal Disorders | Year: 2013

The purpose of this study was to (1) evaluate joint pain and function in knee osteoarthritis (OA) patients treated with a joint-sparing, extracapsular implant and (2) identify patient characteristics that influenced clinical outcomes. This study included 99 patients with symptomatic medial knee OA refractory to conservative care who were treated with the KineSpring Knee Implant System and followed for a mean of 17 months (range, 1.5 to 48 months). All devices were successfully implanted and activated with no intraoperative complications. Statistically significant mean improvements of 56%, 50%, and 38% were observed for Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) Pain, Function, and Stiffness scales, respectively (all P < 0.001). Regardless of gender, age group, body mass index classification, or disease severity, all WOMAC domain scores significantly improved during the postoperative follow-up period. WOMAC clinical success rates were 77.8% for Pain, 77.8% for Function, and 68.7% for Stiffness. Neither gender, age group, body mass index classification, nor disease severity predicted clinical success in any WOMAC domain. In conclusion, the KineSpring System yields clinically meaningful improvements in joint pain and function in patients with medial knee OA. Additionally, unlike joint-altering procedures such as knee arthroplasty or high tibial osteotomy, patient characteristics had little association with postoperative clinical outcomes. © the author(s), publisher and licensee Libertas Academica Ltd.


Miller L.E.,Miller Scientific Consulting Inc. | Miller L.E.,The Jon Block Group | Block J.E.,The Jon Block Group
Clinical Medicine Insights: Arthritis and Musculoskeletal Disorders | Year: 2014

Numerous nonsurgical interventions have been reported to improve symptoms of knee osteoarthritis (OA) over the short term. However, longer follow-up is required to accurately characterize outcomes such as cost effectiveness and delayed arthroplasty. A total of 553 patients with symptomatic knee OA who previously underwent a single 8-week multimodal treatment program were contacted at 1 year (n = 336) or 2 years (n = 217) follow-up. The percentage of patients who underwent knee arthroplasty was 10% at 1 year and 18% at 2 years following program completion. The treatment program was highly cost effective at $12,800 per quality-adjusted life year at 2 years. Cost effectiveness was maintained under a variety of plausible assumptions and regardless of gender, age, body mass index, disease severity, or knee pain severity. In summary, a single 8-week multimodal knee OA treatment program is cost effective and may lower knee arthroplasty utilization through 2 years follow-up. © the authors, publisher and licensee Libertas Academica Limited.


Miller L.E.,Miller Scientific Consulting Inc. | Miller L.E.,The Jon Block Group | Carlton Reckling W.,Si Bone Inc. | Block J.E.,The Jon Block Group
Medical Devices: Evidence and Research | Year: 2013

Background: The sacroiliac joint is a common but under-recognized source of low back and gluteal pain. Patients with degenerative sacroiliitis or sacroiliac joint disruption resistant to nonsurgical treatments may undergo open surgery with sacroiliac joint arthrodesis, although outcomes are mixed and risks are significant. Minimally invasive sacroiliac joint arthrodesis was developed to minimize the risk of iatrogenic injury and to improve patient outcomes compared with open surgery. Methods: Between April 2009 and January 2013, 5319 patients were treated with the iFuse SI Joint Fusion System® for conditions including sacroiliac joint disruption and degenerative sacroiliitis. A database was prospectively developed to record all complaints reported to the manufacturer in patients treated with the iFuse device. Complaints were collected through spontaneous reporting mechanisms in support of ongoing mandatory postmarket surveillance efforts. Results: Complaints were reported in 204 (3.8%) patients treated with the iFuse system. Pain was the most commonly reported clinical complaint (n = 119, 2.2%), with nerve impingement (n = 48, 0.9%) and recurrent sacroiliac joint pain (n = 43, 0.8%) most frequently cited. All other clinical complaints were rare (<0.2%). Ninety-six revision surgeries were performed in 94 (1.8%) patients at a median follow-up of four (range 0-30) months. Revisions were typically performed in the early postoperative period for treatment of a symptomatic malpositioned implant (n = 46, 0.9%) or to correct an improperly sized implant in an asymptomatic patient (n = 10, 0.2%). Revisions in the late postoperative period were performed to treat symptom recurrence (n = 34, 0.6%) or for continued pain of undetermined etiology (n = 6, 0.1%). Conclusion: Analysis of a postmarket product complaints database demonstrates an overall low risk of complaints with the iFuse SI Joint Fusion System in patients with degenerative sacroiliitis or sacroiliac joint disruption. © 2013 Miller et al, publisher and licensee Dove Medical Press Ltd.


Miller L.E.,Miller Scientific Consulting Inc. | Miller L.E.,The Jon Block Group | Sode M.,BioClinica | Fuerst T.,BioClinica | Block J.E.,The Jon Block Group
Clinical Interventions in Aging | Year: 2015

Background: Knee osteoarthritis (OA) is largely attributable to chronic excessive and aberrant joint loading. The purpose of this pilot study was to quantify radiographic changes in subchon- dral bone after treatment with a minimally invasive joint unloading implant (KineSpring® Knee Implant System). Methods: Nine patients with unilateral medial knee OA resistant to nonsurgical therapy were treated with the KineSpring System and followed for 2 years. Main outcomes included Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain, function, and stiff- ness subscores and independent core laboratory determinations of joint space width and fractal signature of the tibial cortex. Results: WOMAC scores, on average, improved by 92% for pain, 91% for function, and 79% for stiffness over the 2-year follow-up period. Joint space width in the medial compart- ment of the treated knee significantly increased from 0.9 mm at baseline to 3.1 mm at 2 years; joint space width in the medial compartment of the untreated knee was unchanged. Fractal signatures of the vertically oriented trabeculae in the medial compartment decreased by 2.8% in the treated knee and increased by 2.1% in the untreated knee over 2 years. No statistically significant fractal signature changes were observed in the horizontally oriented trabeculae in the medial compartment or in the horizontal or vertical trabeculae of the lateral compartment in the treated knee. Conclusion: Preliminary evidence suggests that the KineSpring System may modify knee OA disease progression by increasing joint space width and improving subchondral bone trabecular integrity, thereby reducing pain and improving joint function. © 2015 Miller et al.


Miller L.E.,Miller Scientific Consulting Inc. | Block J.E.,The Jon Block Group
Clinical Medicine Insights: Arthritis and Musculoskeletal Disorders | Year: 2013

We conducted a systematic review and meta-analysis of randomized saline-controlled trials to determine the safety and effcacy of US-approved intra-articular hyaluronic acid (IAHA) injections for symptomatic knee osteoarthritis. A total of 29 studies representing 4,866 unique subjects (IAHA: 2,673, saline: 2,193) were included. IAHA injection resulted in very large treatment effects between 4 and 26 weeks for knee pain and function compared to pre-injection values, with standardized mean difference (SMD) values ranging from 1.07-1.37 (all P< 0.001). Compared to saline controls, SMDs with IAHA ranged from 0.38-0.43 for knee pain and 0.32-0.34 for knee function (all P<0.001). There were no statistically significant differences between IAHA and saline controls for any safety outcome, including serious adverse events (SAEs) (P = 0.12), treatment-related SAEs (P = 1.0), study withdrawal (P = 1.0), and AE-related study withdrawal (P = 0.46). We conclude that intra-articular injection of US-approved HA products is safe and efficacious in patients with symptomatic knee osteoarthritis. © the author(s), publisher and licensee Libertas Academica Ltd.


Strand V.,Stanford University | McIntyre L.F.,New York University | Beach W.R.,Tuckahoe Orthopaedics | Miller L.E.,Miller Scientific Consulting Inc. | And 2 more authors.
Journal of Pain Research | Year: 2015

Background: Intra-articular injection of hyaluronic acid is a common, yet controversial, therapeutic option for patients with knee osteoarthritis (OA). The purpose of this research was to determine the safety and efficacy of US-approved viscosupplements for symptomatic knee OA. Methods: We searched MedLine and EMBase for randomized, sham-controlled trials evaluating safety and/or clinical efficacy of US-approved viscosupplements in patients with symptomatic knee OA. Knee pain severity and knee joint function were assessed at 4 to 13 weeks and 14 to 26 weeks. Safety outcomes included serious adverse events, treatment-related serious adverse events, patient withdrawal, and adverse event-related patient withdrawal occurring at any time during follow-up. Results: A total of 29 studies representing 4,866 unique patients (active: 2,673, control: 2,193) were included. All sham-controlled trials used saline injections as a control. Viscosupplementation resulted in very large treatment effects between 4 and 26 weeks for knee pain and function compared to preinjection values, with standardized mean difference values ranging from 1.07 to 1.37 (allP<0.001). Compared to controls, standardized mean difference with viscosupplementation ranged from 0.38 to 0.43 for knee pain and 0.32 to 0.34 for knee function (all P<0.001). There were no statistically significant differences between viscosupplementation and controls for any safety outcome, with absolute risk differences of 0.7% (95% confidence interval [CI]: –0.2 to 1.5%) for serious adverse events, 0% (95% CI: –0.4 to 0.4%) for treatment-related serious adverse events, 0% (95% CI: –1.6 to 1.6%) for patient withdrawal, and 0.2% (95% CI: –0.4 to 0.8%) for adverse event-related patient withdrawal. Conclusion: Intra-articular injection of US-approved viscosupplements is safe and efficacious through 26 weeks in patients with symptomatic knee OA. © 2015 Strand et al.


Berkoff D.J.,University of North Carolina at Chapel Hill | Miller L.E.,Miller Scientific Consulting Inc. | Miller L.E.,The Jon Block Group | Block J.E.,The Jon Block Group
Clinical Interventions in Aging | Year: 2012

Intra-articular corticosteroid and hyaluronic acid injections provide short-term symptom amelioration for arthritic conditions involving structural damage or degenerative changes in the knee. Conventional palpation-guided anatomical injections frequently result in inaccurate needle placement into extra-articular tissue and adjacent structures. The purpose of this review was to determine the effect of ultrasound guidance on the accuracy of needle placement, clinical outcomes, and cost-effectiveness in comparison with anatomical landmarkguided intra-articular large joint injections, with particular emphasis on the knee. A total of 13 relevant studies were identified; five studied the knee, seven studied the shoulder, one used both the knee and shoulder, and none studied the hip. Ultrasound was used in seven studies; the remaining studies utilized air arthrography, fluoroscopy, magnetic resonance arthrography, or magnetic resonance imaging. Across all studies (using all imaging modalities and all joints), needle placement accuracy ranged from 63% to 100% with ultrasound and from 39% to 100% with conventional anatomical guidance. Imaging guidance improved the accuracy of intraarticular injections of the knee (96.7% versus 81.0%, P < 0.001) and shoulder (97.3% versus 65.4%, P < 0.001). In particular, ultrasound guidance of knee injections resulted in better accuracy than anatomical guidance (95.8% versus 77.8%, P < 0.001), yielding an odds ratio of 6.4(95% confidence interval 2.9-14). Ultrasound guidance notably improves injection accuracy in the target intra-articular joint space of large joints including the knee. The enhanced injection accuracy achieved with ultrasound needle guidance directly improves patient-reported clinical outcomes and cost-effectiveness. © 2012 Berkoff et al, publisher and licensee Dove Medical Press Ltd.


Bhandari M.,McMaster University | Miller L.E.,Miller Scientific Consulting Inc. | Miller L.E.,The Jon Block Group | Block J.E.,The Jon Block Group
Clinical Medicine Insights: Arthritis and Musculoskeletal Disorders | Year: 2012

Surgery is indicated for symptomatic knee osteoarthritis (OA) when conservative measures are unsuccessful. High tibial osteotomy (HTO), unicompartmental knee arthroplasty (UKA), and total knee arthroplasty (TKA) are surgical options intended to relieve knee OA pain and dysfunction. The choice of surgical intervention is dependent on several factors such as disease location, patient age, comorbidities, and activity levels. Regardless of surgical treatment, complications such as infection, loosening or lysis, periprosthetic fracture, and postoperative pain are known risks and are indications for revision surgery. The clinical and economic implications for revision surgery are underappreciated. Over 55,000 revision surgeries were performed in 2010 in the US, with 48% of these revisions in patients under 65 years. Total costs associated with each revision TKA surgery have been estimated to be in excess of $49,000. The current annual economic burden of revision knee OA surgery is $2.7 billion for hospital charges alone. By 2030, assuming a 5-fold increase in the number of revision procedures, this economic burden will exceed $13 billion annually. It is appealing to envision a therapy that could delay or obviate the need for arthroplasty. From an actuarial standpoint, this would have the theoretical downstream effect of substantially reducing the number of revision procedures. Although no known therapies currently meet these criteria, such a breakthrough would have a tremendous impact in lessening the clinical and economic burden of knee OA revision surgery. © the author(s), publisher and licensee Libertas Academica Ltd.

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