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Dive into the research topics where Geoffrey S. Van Thiel is active.

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Featured researches published by Geoffrey S. Van Thiel.


Arthroscopy | 2012

The Role of Platelet-Rich Plasma in Arthroscopic Rotator Cuff Repair: A Systematic Review With Quantitative Synthesis

Jaskarndip Chahal; Geoffrey S. Van Thiel; Nathan A. Mall; Wendell Heard; Bernard R. Bach; Brian J. Cole; Gregory P. Nicholson; Nikhil N. Verma; Daniel B. Whelan; Anthony A. Romeo

PURPOSE Despite the theoretic basis and interest in using platelet-rich plasma (PRP) to improve the potential for rotator cuff healing, there remains ongoing controversy regarding its clinical efficacy. The objective of this systematic review was to identify and summarize the available evidence to compare the efficacy of arthroscopic rotator cuff repair in patients with full-thickness rotator cuff tears who were concomitantly treated with PRP. METHODS We searched the Cochrane Central Register of Controlled Trials, Medline, Embase, and PubMed for eligible studies. Two reviewers selected studies for inclusion, assessed methodologic quality, and extracted data. Pooled analyses were performed using a random effects model to arrive at summary estimates of treatment effect with associated 95% confidence intervals. RESULTS Five studies (2 randomized and 3 nonrandomized with comparative control groups) met the inclusion criteria, with a total of 261 patients. Methodologic quality was uniformly sound as assessed by the Detsky scale and Newcastle-Ottawa Scale. Quantitative synthesis of all 5 studies showed that there was no statistically significant difference in the overall rate of rotator cuff retear between patients treated with PRP and those treated without PRP (risk ratio, 0.77; 95% confidence interval, 0.48 to 1.23). There were also no differences in the pooled Constant score; Simple Shoulder Test score; American Shoulder and Elbow Surgeons score; University of California, Los Angeles shoulder score; or Single Assessment Numeric Evaluation score. CONCLUSIONS PRP does not have an effect on overall retear rates or shoulder-specific outcomes after arthroscopic rotator cuff repair. Additional well-designed randomized trials are needed to corroborate these findings. LEVEL OF EVIDENCE Level III, systematic review of Level I, II, and III studies.


Arthroscopy | 2010

Retrospective analysis of arthroscopic management of glenohumeral degenerative disease.

Geoffrey S. Van Thiel; Steven Sheehan; Rachel M. Frank; Mark A. Slabaugh; Brian J. Cole; Gregory P. Nicholson; Anthony A. Romeo; Nikhil N. Verma

PURPOSE The purpose of this study was to examine the results of arthroscopic debridement for isolated degenerative joint disease of the shoulder. METHODS We retrospectively identified 81 patients who had arthroscopic debridement to treat glenohumeral arthritis. Of these patients, 71 (88%) were available for follow-up. The preoperative Simple Shoulder Test score, American Shoulder and Elbow Surgeons score, Short Form 12 score, visual analog scale score for pain, and range of motion were recorded. These were compared against postoperative scores by use of the statistical paired t test. In addition, patients completed postoperative University of California, Los Angeles; Constant; and Single Assessment Numeric Evaluation scores. Forty-six preoperative radiographs were blindly evaluated and classified. Finally, the need for subsequent shoulder arthroplasty was recorded. RESULTS The mean follow-up for the 55 patients who did not progress to arthroplasty was 27 months. The mean preoperative and postoperative American Shoulder and Elbow Surgeons, Simple Shoulder Test, and pain visual analog scale scores all significantly improved (P < .05). Furthermore, range of motion significantly improved (P < .05) in flexion, abduction, and external rotation. Additional postoperative scores were as follows: University of California, Los Angeles, 28.3; Single Assessment Numeric Evaluation, 71.1; Constant score for affected shoulder, 72.0; and Constant score for unaffected shoulder, 78.5. Of the patients, 16 (22%) underwent arthroplasty at a mean of 10.1 months after debridement. Radiographic review showed that 13 shoulders with a mean joint space of 1.5 mm and grade 2.4 arthrosis went on to have shoulder arthroplasty. In contrast, 33 shoulders with a mean joint space of 2.6 mm and grade 1.9 arthrosis did not go on to have shoulder arthroplasty. CONCLUSIONS Patients with residual joint space and an absence of large osteophytes can avoid arthroplasty and have increased function with decreased pain after arthroscopic debridement for degenerative joint disease. Significant risk factors for failure include the presence of grade 4 bipolar disease, joint space of less than 2 mm, and large osteophytes. LEVEL OF EVIDENCE Level IV, case series.


Arthroscopy | 2012

The role of subacromial decompression in patients undergoing arthroscopic repair of full-thickness tears of the rotator cuff: a systematic review and meta-analysis.

Jaskarndip Chahal; Nathan A. Mall; Peter B. MacDonald; Geoffrey S. Van Thiel; Brian J. Cole; Anthony A. Romeo; Nikhil N. Verma

PURPOSE The purpose of this study was to determine the efficacy of arthroscopic repair of full-thickness rotator cuff tears with and without subacromial decompression. METHODS We searched the Cochrane Central Register of Controlled Trials (third quarter of 2011), Medline (1948 to week 1 of September 2011), and Embase (1980 to week 37 of 2011) for eligible randomized controlled trials. Two reviewers selected studies for inclusion, assessed methodologic quality, and extracted data. Pooled analyses were performed by use of a random effects and relative risk model with computation of 95% confidence intervals. RESULTS We included 4 randomized trials and 373 patients. Methodologic quality was variable as assessed by the CLEAR NPT (Checklist to Evaluate a Report of a Non-pharmacological Trial) tool. One trial showed that there was no difference in disease-specific quality of life (Western Ontario Rotator Cuff questionnaire) between the 2 treatment groups. A meta-analysis of shoulder-specific outcome measures (American Shoulder and Elbow Surgeons or Constant scores) or the rate of reoperation between patients treated with subacromial decompression and those treated without it also showed no statistically significant differences. CONCLUSIONS On the basis of the currently available literature, there is no statistically significant difference in subjective outcome after arthroscopic rotator cuff repair with or without acromioplasty at intermediate follow-up. LEVEL OF EVIDENCE Level I, systematic review of Level I studies.


American Journal of Sports Medicine | 2012

Effects of Serial Sectioning and Repair of Radial Tears in the Lateral Meniscus

Gabriella E. Ode; Geoffrey S. Van Thiel; Samuel A. McArthur; Justin G. Dishkin-Paset; Sue Leurgans; Elizabeth Shewman; Vincent M. Wang; Brian J. Cole

Background: Radial transection of the peripheral fibers of the meniscus could render it nonfunctional; however, the biomechanical consequences of a complete lateral meniscal radial tear and repair in human specimens have not been elucidated. Hypothesis: A complete radial tear will exhibit knee contact mechanics approaching those of total meniscectomy. Repair of complete radial tears will re-create normal load transmission across the joint. Study Design: Controlled laboratory study. Methods: Five matched pairs of fresh-frozen human cadaveric knees were tested in axial compression (800 N) at 2 knee flexion angles (0° and 60°). Six meniscal conditions were sequentially tested: (1) intact lateral meniscus; radial width tears of (2) 50%, (3) 75%, and (4) 100%; (5) meniscal repair; and (6) total meniscectomy. Repairs were pair matched and used either an inside-out or all-inside technique. Tekscan sensors measured tibiofemoral contact pressure, peak contact force, and contact area in the lateral meniscus and medial meniscus. Results: Complete radial tears of the lateral meniscus produced significant increases in mean contact pressure (P = .0001) and decreased contact area (P < .0001) compared with the intact state. This effect was significantly less than that of total meniscectomy (P < .0023). Lesser degrees of radial tears were not significantly different from the intact state (P > .3619). Mean contact pressure after either repair technique was not significantly different from the intact state (P = .2595) or from each other (P = .4000). Meniscal repair produced an increase in contact area compared with a complete tear but was still significantly less than that of the intact meniscus (P < .0001). The medial compartment showed no significant difference between all testing conditions for 0° and 60° of flexion (P ≥ .0650). Conclusion: A complete radial meniscal tear of the lateral meniscus has a detrimental effect on load transmission. Repair improved contact area and pressure. Contact pressures for repaired menisci were not significantly different from the intact state, but contact area was significantly different. Biomechanical performance of repair constructs was equivalent. Clinical Relevance: Repair of complete radial tears improves joint mechanics, potentially decreasing the likelihood of cartilage degeneration.


Journal of Shoulder and Elbow Surgery | 2010

Biomechanical similarities among subscapularis repairs after shoulder arthroplasty

Geoffrey S. Van Thiel; Vincent M. Wang; FanChia Wang; Shane J. Nho; Dana P. Piasecki; Bernard R. Bach; Anthony A. Romeo

HYPOTHESIS Many authors suggest that subscapularis deficiency after shoulder arthroplasty has a negative effect on long-term outcomes. Thus, increasing emphasis has been placed on the technique for repair of the tendon. This study evaluated the biomechanical strength of 3 different repairs: osteotomy, tendon to bone, and a combined method. MATERIALS AND METHODS Twenty-four paired shoulders from deceased donors were prepared for shoulder arthroplasty. The subscapularis tendon was removed/repaired with the lesser tuberosity in the osteotomy group, was removed periosteally in the bone-to-tendon group, and was tenotomized in the combined group. The tendon-to-bone repair used bone tunnels, and the combined construct added tendon-to-tendon fixation. A materials testing system machine was used for cycling. A digital motion analysis system with spatial markers was used for analysis. RESULTS There were no significant differences (P > .05) in age, bone mineral density, or construct thickness. No statistically significant differences (P > .05) in elongation amplitude (P = .67) or cyclic elongation (P = .58) were detected within the constructs or between repair techniques. Failure testing revealed no differences in maximum load, stiffness, or mode of failure. DISCUSSION There remains no consensus about the optimal method of repairing the subscapularis tendon during shoulder arthroplasty. Furthermore, the results of the current study do not support one technique over another with regard to initial fixation properties. All constructs investigated exhibited comparably robust biomechanical performance. Durability may, therefore, be more a result of healing potential than the specific construct chosen.


American Journal of Sports Medicine | 2010

Clinical Outcomes After Microfracture of the Glenohumeral Joint

Rachel M. Frank; Geoffrey S. Van Thiel; Mark A. Slabaugh; Anthony A. Romeo; Brian J. Cole; Nikhil N. Verma

Background Microfracture is an effective surgical treatment for isolated, full-thickness cartilage defects with current data focused on applications in the knee. No studies describing clinical outcomes of patients who have undergone microfracture in the shoulder joint have been reported. Hypothesis Treatment of glenohumeral joint articular defects using microfracture would demonstrate similar short-term clinical outcomes when compared with other joints. Study Design Case series; Level of evidence, 4. Methods From March 2001 to August 2007, 16 patients (17 shoulders) who underwent arthroscopic microfracture of the humeral head and/or glenoid surface were retrospectively reviewed. All patients were examined by an independent, blinded examiner and completed surveys containing the Simple Shoulder Test (SST), American Shoulder and Elbow Score (ASES), and visual analog scale (VAS). Results Two patients were lost to follow-up, for a follow-up rate of 88%. Three patients went on to subsequent shoulder surgery and were considered to have failed results. The mean age was 37.0 years (range, 18-55 years) with an average follow-up of 27.8 months (range, 12.1-89.2 months). The average size of humeral and glenoid defects was 5.07 cm2 (range, 1.0-7.84 cm2) and 1.66 cm2 (range, 0.4-3.75 cm2), respectively. There was a statistically significant decrease from 5.6 ± 1.7 to 1.9 ± 1.4 (P < .01) in VAS after surgery as well as statistically significant improvements (P < .01) in SST (5.7 ± 2.1 to 10.3 ± 1.3) and ASES (44.3 ± 15.3 to 86.3 ± 10.5). Twelve (92.3%) patients claimed they would have the procedure again. Conclusion Microfracture of the glenohumeral joint provides a significant improvement in pain relief and shoulder function in patients with isolated, full-thickness chondral injuries. Longer term studies are required to determine if similar results are maintained over time.


Arthroscopy | 2009

Meniscal Allograft Size Can Be Predicted by Height, Weight, and Gender

Geoffrey S. Van Thiel; Nikhil N. Verma; Adam B. Yanke; Sanjib Basu; Jack Farr; Brian J. Cole

PURPOSE Our purpose was to determine if height, weight, and gender can be used to accurately predict proper meniscal allograft dimensions. METHODS Data were obtained from the Joint Restoration Foundation (AlloSource, Centennial, CO) regarding meniscal size and patient characteristics from meniscal donors. Donor height, weight, sex, age, and anatomic meniscal dimensions were recorded for 930 donor menisci in 664 patients. Multivariate regressions were completed using gender, height, and weight as independent variables and lateral meniscus length, lateral meniscus width, medial meniscus length, and medial meniscus width as dependent variables. The regression formulas were then reapplied to the data in order to produce estimated meniscus dimensions based on donor height, weight, and gender. A 90:10 split of the data was used to validate the regression models. Predicted meniscal size was then compared to actual meniscal size and the results compared to current measurement techniques. RESULTS Regression formulas showed the ability to predict meniscal size based on gender, height, and weight with standard deviations (SDs) equal to or less than current radiographic techniques (SD, 6.4% to 8.2%). Average differences between predicted size and actual size ranged from 5.2% to 6.5% for length and 5.2% to 6.0% for width. Patient height was found to be a much more powerful predictor of meniscal size than patient weight. Data from the 90:10 split of data validated the model on an independent sample. These validated outputs were then compared to contemporary techniques and found to have lower SDs and average error rates in the majority of cases. CONCLUSIONS We have proposed a validated regression model that uses height, weight, and gender variables to accurately predict required allograft meniscal size. We compared it against previously published data for radiographic and magnetic resonance imaging sizing techniques and found it to produce results that were, overall, slightly more accurate. CLINICAL RELEVANCE This model provides a novel method for sizing meniscal allografts.


Arthroscopy | 2011

Biceps tenodesis with interference screw fixation: a biomechanical comparison of screw length and diameter.

Maj Mark A. Slabaugh; Rachel M. Frank; Geoffrey S. Van Thiel; Rebecca Bell; Vincent M. Wang; Scott W. Trenhaile; Matthew T. Provencher; Anthony A. Romeo; Nikhil N. Verma

PURPOSE To evaluate the effect of screw length and diameter on the mechanical properties of biceps tenodesis (BT) with an interference screw in 2 different locations (proximal and distal). METHODS We randomized 42 fresh-frozen human cadaveric shoulders (mean age, 65 ± 8 years) into 6 groups (n = 7): arthroscopic proximal BT using 7 × 15-, 7 × 25-, 8 × 15-, or 8 × 25-mm interference screws or distal subpectoral BT with 7 × 15- or 8 × 15-mm interference screws. Each repaired specimen was mounted onto a materials testing machine, preloaded to 5 N for 2 minutes, cycled from 5 to 70 N for 500 cycles (1 Hz), and loaded to failure (1 mm/s). Displacement during cyclical loading, pullout stiffness, and ultimate load to failure were computed, and the mechanism of failure was noted. RESULTS All failures occurred at the tendon-screw interface. There was no statistically significant difference in ultimate displacement among all groups in the ultimate load to failure, displacement at peak load, and stiffness. CONCLUSIONS There is no difference in ultimate load to failure, displacement at peak load, and stiffness of BT with regard to screw length or diameter at both proximal and distal tenodesis locations. These data would support use of a smaller-diameter and shorter implant for BT both proximally and distally. CLINICAL RELEVANCE The results may serve as a guide to the orthopaedic surgeon performing proximal BT in selecting the appropriate interference screw. When possible, we recommend using the smallest screw size available to minimize risk of stress fracture at the tenodesis site.


American Journal of Sports Medicine | 2010

A Biomechanical Analysis of Anterior Bankart Repair Using Suture Anchors

Shane J. Nho; Rachel M. Frank; Geoffrey S. Van Thiel; Fan Chia Wang; Vincent M. Wang; Matthew T. Provencher; Nikhil N. Verma

Background: Arthroscopic repair of anterior Bankart lesions is typically done with single-loaded suture anchors tied with simple stitch configuration. Hypothesis: The knotless suture anchor will have similar biomechanical properties compared with two types of conventional suture anchors. Study Design: Controlled laboratory study. Methods: Fresh-frozen shoulders were dissected and an anteroinferior Bankart lesion was created. For phase 1, specimens were randomized into either simple stitch (SSA) or knotless suture anchors (KSA) and loaded to failure. For phase 2, specimens were randomized into 1 of 4 repair techniques and cyclically loaded then loaded to failure: (1) SSA, (2) suture anchor with horizontal mattress configuration, (3) double-loaded suture anchor with simple stitch configuration, or (4) KSA. Data recorded included mode of failure, ultimate load to failure, load at 2 mm of displacement, as well as displacement during cyclical loading. Results: For phase 1, the load required to 2 mm displacement of the repair construct was significantly greater in SSA (66.5 ± 21.7 N) than KSA (35.0 ± 12.5 N, P = .02). For phase 2, there was a statistically significant difference in ultimate load to failure among the 4groups, with both the single-loaded suture anchor with simple stitch (184.0 ± 64.5 N), horizontal mattress stitch (189.0 ± 65.3N), and double-loaded suture anchor with simple stitch (216.7 ± 61.7 N) groups having significantly (P < .05) higher loads than the knotless group (103.9 ± 52.8 N). There was no statistically significant difference (P > .05) among the 4 groups in displacement after cyclical loading or load at 2 mm of displacement. Conclusion: Both knotless and simple anchor configurations demonstrated similar single loads to failure (without cycling); however, the knotless device required less single load to displace 2 mm. All repair stitches, including simple, horizontal, and double-loaded performed similarly. Clinical Relevance: The findings may suggest that with cyclical loading up to 25 N there is no difference in gapping greater than 2mm, but a macrotraumatic event may demonstrate a difference in fixation during the initial postoperative period. Additional in vivo studies are needed to determine whether these differences affect the integrity of the repair construct and, ultimately, the clinical outcome.


Arthroscopy | 2013

Transosseous-Equivalent Rotator Cuff Repair: A Systematic Review on the Biomechanical Importance of Tying the Medial Row

Nathan A. Mall; Andrew S. Lee; Jaskarndip Chahal; Geoffrey S. Van Thiel; Anthony A. Romeo; Nikhil N. Verma; Brian J. Cole

PURPOSE Double-row and transosseous-equivalent repair techniques have shown greater strength and improved healing than single-row techniques. The purpose of this study was to determine whether tying of the medial-row sutures provides added stability during biomechanical testing of a transosseous-equivalent rotator cuff repair. METHODS We performed a systematic review of studies directly comparing biomechanical differences. RESULTS Five studies met the inclusion and exclusion criteria. Of the 5 studies, 4 showed improved biomechanical properties with tying the medial-row anchors before bringing the sutures laterally to the lateral-row anchors, whereas the remaining study showed no difference in contact pressure, mean failure load, or gap formation with a standard suture bridge with knots tied at the medial row compared with knotless repairs. CONCLUSIONS The results of this systematic review and quantitative synthesis indicate that the biomechanical factors ultimate load, stiffness, gap formation, and contact area are significantly improved when medial knots are tied as part of a transosseous-equivalent suture bridge construct compared with knotless constructs. Further studies comparing the clinical healing rates and functional outcomes between medial knotted and knotless repair techniques are needed. CLINICAL RELEVANCE This review indicates that biomechanical factors are improved when the medial row of a transosseous-equivalent rotator cuff is tied compared with a knotless repair. However, this has not been definitively proven to translate to improved healing rates clinically.

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Brian J. Cole

University of Connecticut

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Nikhil N. Verma

Naval Medical Center San Diego

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Bernard R. Bach

Rush University Medical Center

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Vincent M. Wang

Rush University Medical Center

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Rachel M. Frank

University of Colorado Denver

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Nathan A. Mall

Rush University Medical Center

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