Melvin Rosenwasser - Academia.edu (original) (raw)

Papers by Melvin Rosenwasser

Journal of Arthroplasty, Feb 1, 2008

Journal of Arthroplasty, Sep 1, 2008

ABSTRACT The Displaced Femoral (neck fracture) Arthroplasty Consortium for Treatment and Outcomes... more ABSTRACT The Displaced Femoral (neck fracture) Arthroplasty Consortium for Treatment and Outcomes study is a prospective, multicenter randomized clinical trial comparing hemiarthroplasty to total hip arthroplasty (THA) in the treatment of displaced femoral neck fractures in previously independent patients. Primary outcomes were measured at 6, 12, and 24 months with the Short Form-36 (SF-36), Western Ontario and McMaster Osteoarthritis Index (WOMAC), and the Harris Hip Score and the Timed "Up & Go" Test. Forty subjects were enrolled. At 24 months, THA patients had significantly less pain on the SF-36 subscale than hemiarthroplasty patients (54.8 +/- 7.9 vs 44.7 +/- 10.5, P = .04) and scored significantly better on the SF-36 mental health subscale (54.9 +/- 9.4 vs 40.9 +/- 10.3, P = .006). Total hip arthroplasty patients also had superior WOMAC function scores (81.8 +/- 10.2 vs 65.1 +/- 18.1, P = .03). Significant differences in outcomes, without a significantly greater incidence of complications, suggest THA is a valuable treatment option for the active elderly hip fracture population.

Acta Orthopaedica Belgica, 2021

Approximately 30% of all upper extremity fractures are elbow fractures which may result elbow sti... more Approximately 30% of all upper extremity fractures are elbow fractures which may result elbow stiffness. This study aimed to investigate the efficacy of onaBotulinum Toxin type A injection to prevent post-traumatic pain and elbow-stiffness. All patients were included who presented to a single surgeon with supracondylar/ intraarticular distal humerus fractures, proximal ulna and radius fractures. The study was developed in a randomized placebo controlled study between 2003-2007. The Disabilities of the Arm, Shoulder, and Hand (DASH) score as well as the arc-of-motion (AOM) were assessed after three, six, twelve-months and final follow up for evaluation. Of the 31-patients included, 15-patients (48.4%) received Botox injections. In all patients no complication was observed when injecting a dosage 100-units for the brachialis and biceps brachii muscles. Furthermore, it was an effective method to prevent post-traumatic elbow stiffness, lasting six- months. Significant differences in DAS...

Foot & Ankle Orthopaedics, 2020

Category: Trauma; Ankle Introduction/Purpose: Ankle fractures (AFx) are the most common foot and ... more Category: Trauma; Ankle Introduction/Purpose: Ankle fractures (AFx) are the most common foot and ankle fracture seen at hospitals in the United States, and are undoubtedly costly to patients. Quantification of the costs of fractures and their associated treatments has garnered increased attention in orthopedics in recent years through cost-effectiveness analysis. However, literature pertaining to AFx’s almost never reports on the indirect costs of AFx’s, and thus fails to accurately assess the true value of treatments. The purpose of this study was to prospectively assess the direct and indirect costs of AFx’s in operatively and nonoperatively treated patients. Secondary analysis included evaluation of the composition of indirect cost, the duration these costs are endured, and the factors that influence their magnitude. Methods: A prospective observational single-center study was performed. Adult patients presenting for initial consult for an AFx that could speak English or Spanish ...

World Journal of Orthopedics, 2019

Hand (New York, N.Y.), 2018

The aim of this study was to compare the complete visible surface area of the radial head, neck, ... more The aim of this study was to compare the complete visible surface area of the radial head, neck, and coronoid in the Kaplan and Kocher approaches to the lateral elbow. The hypothesis was that the Kaplan approach would afford greater visibility due to the differential anatomy of the intermuscular planes. Ten cadavers were dissected with the Kaplan and Kocher approaches, and the visible surface area was measured in situ using a 3-dimensional digitizer. Six measurements were taken for each approach by 2 surgeons, and the mean of these measurements were analyzed. The mean surface area visible with the lateral collateral ligament (LCL) preserved in the Kaplan approach was 616.6 mmin comparison with the surface area of 136.2 mmvisible in the Kocher approach when the LCL was preserved. Using a 2-way analysis of variance, the difference between these 2 approaches was statistically significant. When the LCL complex was incised in the Kocher approach, the average visible surface area of the K...

American journal of orthopedics (Belle Mead, N.J.), 2015

The isoelastic ultrahigh-molecular-weight polyethylene tension band may be considered an alternat... more The isoelastic ultrahigh-molecular-weight polyethylene tension band may be considered an alternative to stainless steel wire for tension band fixation of olecranon fractures. In this article, we present our technique using this isoelastic tension band and describe the outcomes of 7 patients who underwent open reduction and internal fixation of closed, displaced olecranon fractures with minimal or no articular surface comminution. We reviewed medical records and performed physical examinations and functional assessments. Anatomical reduction was maintained in all elbows through union. Physical examination measurements indicated nominal side-to-side differences in motion and strength. Mean Broberg and Morrey elbow score was good (92/100), and mean (SD) Disabilities of the Arm, Shoulder, and Hand score was 12.6 (17.2). One patient had a minor degree of hardware irritation at longest follow-up but did not request hardware removal. One patient underwent implant removal for a symptomatic ...

Instructional course lectures, 2009

Arthritis of the basal joint of the thumb is a condition that is becoming even more common as lon... more Arthritis of the basal joint of the thumb is a condition that is becoming even more common as longevity increases and more people have active lifestyles in later life. The role of new hyaluronase-based injectable agents is evolving. A number of surgical procedures are effective in treating early-stage arthritis; the commonly performed trapezium resection and ligament reconstruction procedures have been modified by using limited-incision approaches, arthroscopic assistance, and bioengineered materials, as well as metacarpal repositioning osteotomy.

Joint Destruction in Arthritis and Osteoarthritis, 1993

A canine experimental model of osteoarthritis (OA), generated by arthroscopic transection of the ... more A canine experimental model of osteoarthritis (OA), generated by arthroscopic transection of the anterior cruciate ligament (ACL) of the knee, was used to investigate the in vivo effects of the NSAID naproxen on the course of cartilage degeneration. The drug was given at the time of surgery, or from before surgery, and for 16 weeks after surgery. Analysis of the articular cartilage showed the naproxen was able to significantly suppress the decrease in proteoglycan content and metalloproteinase activities. The results indicate that pharmaceutical agents have the potential to modulate the progression of degenerative joint disease.

Techniques in Hand & Upper Extremity Surgery, 2011

Journal of Orthopaedic Trauma, 2012

There is no consensus on the surgical management of unstable distal radius fractures. In this sys... more There is no consensus on the surgical management of unstable distal radius fractures. In this systematic review and meta-analysis, we pool data from trials comparing external fixation and open reduction and internal fixation (ORIF) for this injury. We searched electronic databases (including MEDLINE, EMBASE, and SCOPUS) and conference proceedings from 1950 to 2009 in the English literature. We pooled data from 12 trials totaling 1011 patients (491 fractures treated with external fixation and 520 with ORIF). All randomized studies of external fixation to ORIF for unstable distal radius fractures were considered, and nonrandomized trials were included if and only if they directly compared external fixation with ORIF. Two authors independently extracted data from all eligible studies, including patient characteristics, sample size, fracture type, length of follow-up, intervention, and outcomes. Continuous variables were pooled across studies using the method of standard mean differences (SMD) or effect size. ORIF demonstrated significantly better Disabilities of the Arm, Shoulder, and Hand scores (SMD, 0.28; 95% confidence interval, 0.03-0.53; P = 0.03), recovery of forearm supination (SMD, 0.23; 95% CI, 0.08-0.38; P = 0.003), and restoration of volar tilt (SMD, 0.53; 95% CI, 0.34-0.72; P < 0.00001). However, external fixation resulted in significantly better grip strength (SMD, -10.32; 95% CI, -16.36 to -4.28; P = 0.0008), and subgroup analyses of randomized studies showed external fixation yielded better wrist flexion (SMD, -0.38; 95% CI, -0.58 to -0.17; P = 0.0004). For surgical fixation of unstable distal radius fractures, ORIF yields significantly better functional outcomes, forearm supination, and restoration of anatomic volar tilt. However, external fixation results in better grip strength, wrist flexion, and remains a viable surgical alternative. Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.

Journal of Orthopaedic Research, 1994

The changes in the tensile mechanical properties and biochemical composition of the superficial z... more The changes in the tensile mechanical properties and biochemical composition of the superficial zone of articular cartilage were examined in a canine model of early osteoarthritis generated by transection of the anterior cruciate ligament. Sixteen weeks following ligament transection, the tensile stiffness of the articular cartilage was decreased by 44% and the ion‐induced stress relaxation of the tissue was increased by 57% compared with the contralateral control. Biochemical analyses indicated that the water content of the experimental tissue was increased by 13%, which was reflected as an apparent 37% decrease in the proteoglycan content and a 36% decrease in the collagen content (expressed per wet weight). The hydroxypyridinium crosslink density was decreased in the experimental tissue by 11%. A significant negative correlation was found between the ion‐induced stress relaxation and the hydroxypyridinium crosslink density in both control tissue (R = −0.56) and experimental tissu...

Journal of Orthopaedic Research, 1991

We measured the in situ biomechanical properties of knee joint cartilage from five species (bovin... more We measured the in situ biomechanical properties of knee joint cartilage from five species (bovine, canine, human, monkey, and rabbit) to examine the biomechanical relevance of animal models of human knee joint injuries and osteoarthritis. In situ biphasic creep indentation experiments were performed to simultaneously determine all three intrinsic material coefficients (aggregate modulus, Poisson's ratio, and permeability) of the cartilage as represented by the linear KLM biphasic model. In addition, we also assessed the effects of load bearing on these intrinsic properties at “high” and “low” weight‐bearing regions on the distal femur. Our results indicate that significant differences exist in some of these material properties among species and sites. The aggregate modulus of the anterior patellar groove within each species is the lowest among all sites tested, and the permeability of the patellar groove cartilage is the highest and does not vary among species. Similarly, the P...

The Journal of Hand Surgery, 2012

We compare scaphoid excision and 4-bone arthrodesis (FBA) with proximal row carpectomy (PRC) in t... more We compare scaphoid excision and 4-bone arthrodesis (FBA) with proximal row carpectomy (PRC) in terms of contact pressure, area, and location. Six cadaveric forearms underwent simulated FBA with K-wires. We measured pressures in the radiocarpal joint with Fuji contact film after we applied a 200-N load via the wrist tendons with the wrist in neutral, flexion, and extension. We repeated the experiment after excising the lunate and triquetrum, to create a PRC in the same specimens. Contact pressure in the PRC wrist was significantly greater, by 25%, compared with the FBA wrist for all wrist positions. The PRC wrist had a significantly smaller contact area, by 43%, compared with the FBA wrist. In the FBA wrist, lunate contact was more dorsal in flexion but more volar in extension. In the PRC wrist, capitate contact was more dorsal and radial in flexion, whereas the contact was more volar and ulnar in extension. Comparing contact location, FBA contact was significantly more ulnar than PRC contact in wrist flexion. We found no significant difference in contact translation (the distance between the contact locations in the positions of wrist flexion and extension) for the lunate in FBA or the capitate in PRC. The FBA wrist has significantly lower contact pressure (P < .001), greater contact area (P < .001), and equal contact translation compared with the PRC wrist. These qualities may make FBA less susceptible to degeneration over time. By advancing our understanding of the biomechanics of both wrist procedures, we may better tailor them to the individual patient. Current biomechanical evidence is lacking for common motion-preserving procedures for wrist arthritis. Comparing contact pressure, area, and location provides a biomechanical basis of our clinical understanding of these surgeries.

The Journal of Hand Surgery, 2000

The biochemical composition and biomechanical properties of articular cartilage from 53 human thu... more The biochemical composition and biomechanical properties of articular cartilage from 53 human thumb carpometacarpal (CMC) joints from cadavers aged 20 to 79 years were measured and studied in normal, mildly fibrillated, and advanced osteoarthritic (OA) joints. Statistical analyses were performed to determine the correlations between the compositional measures and biomechanical properties. For these CMC joint tissues we found that water content increased, proteoglycan content decreased, and collagen content per dry weight remained unaltered with progression of OA degeneration. We also found that with disease progression, as defined by an OA staging score, the aggregate modulus (ie, compressive stiffness) decreased, along with an unexpected moderate decrease in permeability. This latter finding appears to be specific to CMC cartilage degeneration since articular cartilage from knees and hips generally demonstrates an increase in permeability with water content and OA score. Correlations between biochemical composition and biomechanical properties were found to be stronger in joints with OA than in joints without OA. This finding suggests that OA changes in biochemical composition, relative to baseline normal values, directly affect the biomechanical properties of cartilage, even though the baseline compositional values themselves do not directly determine the magnitude of the biomechanical properties in normal tissue.

The Journal of Hand Surgery, 2009

The Journal of Hand Surgery, 1998

The articular topography of 46 osteoarthritic thumb carpometacarpal joints was quantitatively ana... more The articular topography of 46 osteoarthritic thumb carpometacarpal joints was quantitatively analyzed, as well as variations with regard to gender, age, site, and anatomic osteoarthritic stage. It was found that for osteoarthritic thumb carpometacarpal joints,(1) the opposing ...

The Journal of Hand Surgery, 2006

Journal of Arthroplasty, Feb 1, 2008

Journal of Arthroplasty, Sep 1, 2008

ABSTRACT The Displaced Femoral (neck fracture) Arthroplasty Consortium for Treatment and Outcomes... more ABSTRACT The Displaced Femoral (neck fracture) Arthroplasty Consortium for Treatment and Outcomes study is a prospective, multicenter randomized clinical trial comparing hemiarthroplasty to total hip arthroplasty (THA) in the treatment of displaced femoral neck fractures in previously independent patients. Primary outcomes were measured at 6, 12, and 24 months with the Short Form-36 (SF-36), Western Ontario and McMaster Osteoarthritis Index (WOMAC), and the Harris Hip Score and the Timed "Up & Go" Test. Forty subjects were enrolled. At 24 months, THA patients had significantly less pain on the SF-36 subscale than hemiarthroplasty patients (54.8 +/- 7.9 vs 44.7 +/- 10.5, P = .04) and scored significantly better on the SF-36 mental health subscale (54.9 +/- 9.4 vs 40.9 +/- 10.3, P = .006). Total hip arthroplasty patients also had superior WOMAC function scores (81.8 +/- 10.2 vs 65.1 +/- 18.1, P = .03). Significant differences in outcomes, without a significantly greater incidence of complications, suggest THA is a valuable treatment option for the active elderly hip fracture population.

Acta Orthopaedica Belgica, 2021

Approximately 30% of all upper extremity fractures are elbow fractures which may result elbow sti... more Approximately 30% of all upper extremity fractures are elbow fractures which may result elbow stiffness. This study aimed to investigate the efficacy of onaBotulinum Toxin type A injection to prevent post-traumatic pain and elbow-stiffness. All patients were included who presented to a single surgeon with supracondylar/ intraarticular distal humerus fractures, proximal ulna and radius fractures. The study was developed in a randomized placebo controlled study between 2003-2007. The Disabilities of the Arm, Shoulder, and Hand (DASH) score as well as the arc-of-motion (AOM) were assessed after three, six, twelve-months and final follow up for evaluation. Of the 31-patients included, 15-patients (48.4%) received Botox injections. In all patients no complication was observed when injecting a dosage 100-units for the brachialis and biceps brachii muscles. Furthermore, it was an effective method to prevent post-traumatic elbow stiffness, lasting six- months. Significant differences in DAS...

Foot & Ankle Orthopaedics, 2020

Category: Trauma; Ankle Introduction/Purpose: Ankle fractures (AFx) are the most common foot and ... more Category: Trauma; Ankle Introduction/Purpose: Ankle fractures (AFx) are the most common foot and ankle fracture seen at hospitals in the United States, and are undoubtedly costly to patients. Quantification of the costs of fractures and their associated treatments has garnered increased attention in orthopedics in recent years through cost-effectiveness analysis. However, literature pertaining to AFx’s almost never reports on the indirect costs of AFx’s, and thus fails to accurately assess the true value of treatments. The purpose of this study was to prospectively assess the direct and indirect costs of AFx’s in operatively and nonoperatively treated patients. Secondary analysis included evaluation of the composition of indirect cost, the duration these costs are endured, and the factors that influence their magnitude. Methods: A prospective observational single-center study was performed. Adult patients presenting for initial consult for an AFx that could speak English or Spanish ...

World Journal of Orthopedics, 2019

Hand (New York, N.Y.), 2018

The aim of this study was to compare the complete visible surface area of the radial head, neck, ... more The aim of this study was to compare the complete visible surface area of the radial head, neck, and coronoid in the Kaplan and Kocher approaches to the lateral elbow. The hypothesis was that the Kaplan approach would afford greater visibility due to the differential anatomy of the intermuscular planes. Ten cadavers were dissected with the Kaplan and Kocher approaches, and the visible surface area was measured in situ using a 3-dimensional digitizer. Six measurements were taken for each approach by 2 surgeons, and the mean of these measurements were analyzed. The mean surface area visible with the lateral collateral ligament (LCL) preserved in the Kaplan approach was 616.6 mmin comparison with the surface area of 136.2 mmvisible in the Kocher approach when the LCL was preserved. Using a 2-way analysis of variance, the difference between these 2 approaches was statistically significant. When the LCL complex was incised in the Kocher approach, the average visible surface area of the K...

American journal of orthopedics (Belle Mead, N.J.), 2015

The isoelastic ultrahigh-molecular-weight polyethylene tension band may be considered an alternat... more The isoelastic ultrahigh-molecular-weight polyethylene tension band may be considered an alternative to stainless steel wire for tension band fixation of olecranon fractures. In this article, we present our technique using this isoelastic tension band and describe the outcomes of 7 patients who underwent open reduction and internal fixation of closed, displaced olecranon fractures with minimal or no articular surface comminution. We reviewed medical records and performed physical examinations and functional assessments. Anatomical reduction was maintained in all elbows through union. Physical examination measurements indicated nominal side-to-side differences in motion and strength. Mean Broberg and Morrey elbow score was good (92/100), and mean (SD) Disabilities of the Arm, Shoulder, and Hand score was 12.6 (17.2). One patient had a minor degree of hardware irritation at longest follow-up but did not request hardware removal. One patient underwent implant removal for a symptomatic ...

Instructional course lectures, 2009

Arthritis of the basal joint of the thumb is a condition that is becoming even more common as lon... more Arthritis of the basal joint of the thumb is a condition that is becoming even more common as longevity increases and more people have active lifestyles in later life. The role of new hyaluronase-based injectable agents is evolving. A number of surgical procedures are effective in treating early-stage arthritis; the commonly performed trapezium resection and ligament reconstruction procedures have been modified by using limited-incision approaches, arthroscopic assistance, and bioengineered materials, as well as metacarpal repositioning osteotomy.

Joint Destruction in Arthritis and Osteoarthritis, 1993

A canine experimental model of osteoarthritis (OA), generated by arthroscopic transection of the ... more A canine experimental model of osteoarthritis (OA), generated by arthroscopic transection of the anterior cruciate ligament (ACL) of the knee, was used to investigate the in vivo effects of the NSAID naproxen on the course of cartilage degeneration. The drug was given at the time of surgery, or from before surgery, and for 16 weeks after surgery. Analysis of the articular cartilage showed the naproxen was able to significantly suppress the decrease in proteoglycan content and metalloproteinase activities. The results indicate that pharmaceutical agents have the potential to modulate the progression of degenerative joint disease.

Techniques in Hand & Upper Extremity Surgery, 2011

Journal of Orthopaedic Trauma, 2012

There is no consensus on the surgical management of unstable distal radius fractures. In this sys... more There is no consensus on the surgical management of unstable distal radius fractures. In this systematic review and meta-analysis, we pool data from trials comparing external fixation and open reduction and internal fixation (ORIF) for this injury. We searched electronic databases (including MEDLINE, EMBASE, and SCOPUS) and conference proceedings from 1950 to 2009 in the English literature. We pooled data from 12 trials totaling 1011 patients (491 fractures treated with external fixation and 520 with ORIF). All randomized studies of external fixation to ORIF for unstable distal radius fractures were considered, and nonrandomized trials were included if and only if they directly compared external fixation with ORIF. Two authors independently extracted data from all eligible studies, including patient characteristics, sample size, fracture type, length of follow-up, intervention, and outcomes. Continuous variables were pooled across studies using the method of standard mean differences (SMD) or effect size. ORIF demonstrated significantly better Disabilities of the Arm, Shoulder, and Hand scores (SMD, 0.28; 95% confidence interval, 0.03-0.53; P = 0.03), recovery of forearm supination (SMD, 0.23; 95% CI, 0.08-0.38; P = 0.003), and restoration of volar tilt (SMD, 0.53; 95% CI, 0.34-0.72; P < 0.00001). However, external fixation resulted in significantly better grip strength (SMD, -10.32; 95% CI, -16.36 to -4.28; P = 0.0008), and subgroup analyses of randomized studies showed external fixation yielded better wrist flexion (SMD, -0.38; 95% CI, -0.58 to -0.17; P = 0.0004). For surgical fixation of unstable distal radius fractures, ORIF yields significantly better functional outcomes, forearm supination, and restoration of anatomic volar tilt. However, external fixation results in better grip strength, wrist flexion, and remains a viable surgical alternative. Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.

Journal of Orthopaedic Research, 1994

The changes in the tensile mechanical properties and biochemical composition of the superficial z... more The changes in the tensile mechanical properties and biochemical composition of the superficial zone of articular cartilage were examined in a canine model of early osteoarthritis generated by transection of the anterior cruciate ligament. Sixteen weeks following ligament transection, the tensile stiffness of the articular cartilage was decreased by 44% and the ion‐induced stress relaxation of the tissue was increased by 57% compared with the contralateral control. Biochemical analyses indicated that the water content of the experimental tissue was increased by 13%, which was reflected as an apparent 37% decrease in the proteoglycan content and a 36% decrease in the collagen content (expressed per wet weight). The hydroxypyridinium crosslink density was decreased in the experimental tissue by 11%. A significant negative correlation was found between the ion‐induced stress relaxation and the hydroxypyridinium crosslink density in both control tissue (R = −0.56) and experimental tissu...

Journal of Orthopaedic Research, 1991

We measured the in situ biomechanical properties of knee joint cartilage from five species (bovin... more We measured the in situ biomechanical properties of knee joint cartilage from five species (bovine, canine, human, monkey, and rabbit) to examine the biomechanical relevance of animal models of human knee joint injuries and osteoarthritis. In situ biphasic creep indentation experiments were performed to simultaneously determine all three intrinsic material coefficients (aggregate modulus, Poisson's ratio, and permeability) of the cartilage as represented by the linear KLM biphasic model. In addition, we also assessed the effects of load bearing on these intrinsic properties at “high” and “low” weight‐bearing regions on the distal femur. Our results indicate that significant differences exist in some of these material properties among species and sites. The aggregate modulus of the anterior patellar groove within each species is the lowest among all sites tested, and the permeability of the patellar groove cartilage is the highest and does not vary among species. Similarly, the P...

The Journal of Hand Surgery, 2012

We compare scaphoid excision and 4-bone arthrodesis (FBA) with proximal row carpectomy (PRC) in t... more We compare scaphoid excision and 4-bone arthrodesis (FBA) with proximal row carpectomy (PRC) in terms of contact pressure, area, and location. Six cadaveric forearms underwent simulated FBA with K-wires. We measured pressures in the radiocarpal joint with Fuji contact film after we applied a 200-N load via the wrist tendons with the wrist in neutral, flexion, and extension. We repeated the experiment after excising the lunate and triquetrum, to create a PRC in the same specimens. Contact pressure in the PRC wrist was significantly greater, by 25%, compared with the FBA wrist for all wrist positions. The PRC wrist had a significantly smaller contact area, by 43%, compared with the FBA wrist. In the FBA wrist, lunate contact was more dorsal in flexion but more volar in extension. In the PRC wrist, capitate contact was more dorsal and radial in flexion, whereas the contact was more volar and ulnar in extension. Comparing contact location, FBA contact was significantly more ulnar than PRC contact in wrist flexion. We found no significant difference in contact translation (the distance between the contact locations in the positions of wrist flexion and extension) for the lunate in FBA or the capitate in PRC. The FBA wrist has significantly lower contact pressure (P < .001), greater contact area (P < .001), and equal contact translation compared with the PRC wrist. These qualities may make FBA less susceptible to degeneration over time. By advancing our understanding of the biomechanics of both wrist procedures, we may better tailor them to the individual patient. Current biomechanical evidence is lacking for common motion-preserving procedures for wrist arthritis. Comparing contact pressure, area, and location provides a biomechanical basis of our clinical understanding of these surgeries.

The Journal of Hand Surgery, 2000

The biochemical composition and biomechanical properties of articular cartilage from 53 human thu... more The biochemical composition and biomechanical properties of articular cartilage from 53 human thumb carpometacarpal (CMC) joints from cadavers aged 20 to 79 years were measured and studied in normal, mildly fibrillated, and advanced osteoarthritic (OA) joints. Statistical analyses were performed to determine the correlations between the compositional measures and biomechanical properties. For these CMC joint tissues we found that water content increased, proteoglycan content decreased, and collagen content per dry weight remained unaltered with progression of OA degeneration. We also found that with disease progression, as defined by an OA staging score, the aggregate modulus (ie, compressive stiffness) decreased, along with an unexpected moderate decrease in permeability. This latter finding appears to be specific to CMC cartilage degeneration since articular cartilage from knees and hips generally demonstrates an increase in permeability with water content and OA score. Correlations between biochemical composition and biomechanical properties were found to be stronger in joints with OA than in joints without OA. This finding suggests that OA changes in biochemical composition, relative to baseline normal values, directly affect the biomechanical properties of cartilage, even though the baseline compositional values themselves do not directly determine the magnitude of the biomechanical properties in normal tissue.

The Journal of Hand Surgery, 2009

The Journal of Hand Surgery, 1998

The articular topography of 46 osteoarthritic thumb carpometacarpal joints was quantitatively ana... more The articular topography of 46 osteoarthritic thumb carpometacarpal joints was quantitatively analyzed, as well as variations with regard to gender, age, site, and anatomic osteoarthritic stage. It was found that for osteoarthritic thumb carpometacarpal joints,(1) the opposing ...

The Journal of Hand Surgery, 2006