Knee and ankle injuries continue to be ever present at all levels of athletic participation. A relatively recent approach in injury intervention is the use of prophylactic knee braces (PKB) and ankle stabilizers (AS). Prophylactic braces are used to reduce the frequency and severity of injuries in a cost effective manner, but their clinical efficacy has been questioned. Specific to PKB, there is little agreement among the results of studies completed to date as to their effectiveness in reducing the incidence of knee injuries. This is attributed to a lack of control of confounding variables that mitigate the interpretive findings of many studies. Although the clinical research regarding AS is limited, it appears that they are effective in reducing the incidence of acute ankle injuries. Recommendations for future study as well as considerations for clinical research analysis are presented.
Michael R. Sitler
Carolyn Jimenez, Mayra Santiago, Michael Sitler, Guenther Boden and Carol Homko
Little is known about the acute effects of resistance exercise on insulin sensitivity in people with type 1 diabetes.
Repeated-measures design with 2 independent variables: group (exercise and nonexercise control) and time (preexercise and 12 and 36 h postexercise).
General Clinical Research Center, Temple University Hospital, Philadelphia, PA.
14 physically active subjects (11 men and 3 women) with type 1 diabetes.
The exercise group completed 5 sets of 6 repetitions of strenuous (80% 1-RM) quadriceps and hamstring exercises while the control group performed only activities of daily Living.
Main Outcome Measures:
Insulin sensitivity was assessed with the euglycemic-hyperinsulinemic-clamp technique preexercise and 12 and 36 h postexercise.
Insulin-sensitivity values were not significantly different between the exercise and control groups (P = .92) or over time (P = .67).
A single bout of strenuous resistance exercise does not alter insulin sensitivity in people with type 1 diabetes.
Christine Bocchinfuso, Michael R. Sitler and Iris F. Kimura
The purpose of this study was to compare the effects of two semirigid prophylactic ankle stabilizers on vertical jump, 80-ft sprint, shuttle run, and four-point run performance. Eight male and seven female high school basketball players, who denied prior ankle injury and prophylactic ankle stabilizer experience, completed the four performance events under the conditions of Active Ankle Training Brace, Aircast SportStirrup, and nonbraced control. Data analyses consisted of four 1 × 3 ANOVAs with repeated measures on the independent variable of brace condition. Results of the analysis revealed no significant differences among the experimental conditions for any of the performance events tested. In conclusion, the Active Ankle Training Brace and Aircast SportStirrup did not facilitate or adversely affect performance involving speed, agility, and vertical jump of high school basketball players.
Alison Locke, Michael Sitler, Christopher Aland and Iris Kimura
The purpose of this study was to determine the effect of a softshell prophylactic ankle stabilizer (PAS) on performance in events involving speed, agility, and vertical jump during long-term use. The events examined were the 24.384-m sprint, 12.192-m shuttle ran, and vertical jump. Subjects were high school basketball players who were randomly assigned to either a PAS (n = 11) or a nonbraced control (n = 13) group. Results of the study revealed that the softshell PAS had no significant effect on any of the three performance events tested over a 3-month basketball season. However, there was a significant difference in 24.384-m sprint and 12.192-m shuttle run times across test sessions regardless of treatment group. In conclusion, the softshell PAS neither enhanced nor inhibited performance in activities involving speed, agility, or vertical jump during long-term use.
Michael Ra, Michael Sitler, Jeff Ryan, Raymond Moyer, Paul Marchetto, John Kelly and Iris Kimura
Chondral lesions often occur in the knee as isolated defects or part of more complex injuries. Articular cartilage defects decrease the ability of the knee to sustain weight-bearing loads and may accelerate degeneration of the joint when left untreated. The purpose of this study was to determine the clinical, functional, and radiographic outcome of arthroscopic abrasion chondroplasty of the knee. The Articular Cartilage Rating System was used to assess the location, size, depth, and description of the articular lesion. The Standard Knee Evaluation Form and Cincinnati Knee Rating Scale were used to assess the clinical, functional, and radiographic outcome of the procedure. Average time to postsurgery follow-up was 46 ± 26.69 months. Within the constraints of the present study, arthroscopic abrasion chondroplasty of the knee had a favorable clinical, functional, and radiographic outcome. However, more study is needed with larger samples and longer follow-up before definitive conclusions about the efficacy of the procedure can be made.
Jeffrey B. Driban, Easwaran Balasubramanian, Mamta Amin, Michael R. Sitler, Marvin C. Ziskin and Mary F. Barbe
Joint trauma is a risk factor for osteoarthritis (OA), which is becoming an increasingly important orthopedic concern for athletes and nonathletes alike. For advances in OA prevention, diagnosis, and treatment to occur, a greater understanding of the biochemical environment of the affected joint is needed.
To demonstrate the potential of a biochemical technique to enhance our understanding of and diagnostic capabilities for osteoarthritis.
Outpatient orthopedic practice.
8 subjects: 4 OA-knee participants (65 ± 6 y of age) and 4 normal-knee participants (54 ± 10 y) with no history of knee OA based on bilateral standing radiographs.
The independent variable was group (OA knee, normal knee).
Main Outcome Measures:
16 knee synovial-protein concentrations categorized as follows: 4 as pro-inflammatory, or catabolic, cytokines; 5 as anti-inflammatory, or protective, cytokines; 3 as catabolic enzymes; 2 as tissue inhibitors of metalloproteinases [TIMPs]; and 2 as adipokines.
Two anti-inflammatory cytokines (interleukin [IL]-13 and osteoprotegerin) and a pro-inflammatory cytokine (IL-1β) were significantly lower in the OA knees. Two catabolic enzymes (matrix metalloproteinase [MMP]-2 and MMP-3) were significantly elevated in OA knees. TIMP-2, an inhibitor of MMPs, was significantly elevated in OA knees.
Six of the 16 synovial-fluid proteins were significantly different between OA knees and normal knees in this study. Future research using a similar multiplex ELISA approach or other proteomic techniques may enable researchers and clinicians to develop more accurate biochemical profiles of synovial fluid to help diagnose OA, identify subsets of OA or individual characteristics, guide clinical decisions, and identify patients at risk for OA after knee injury.
Jeffrey B. Driban, Nicole Cattano, Easwaran Balasubramanian, Michael R. Sitler, Mamta Amin, Joseph Glutting and Mary F. Barbe
Context: To better understand why a knee develops osteoarthritis after joint trauma we need to assess the local biochemical changes. Unfortunately, it is challenging to obtain synovial fluid from a knee with no effusion. Objective: To describe the authors' protocol for aspirating synovial fluid from noneffused knees. Second, they demonstrate the validity of this method by evaluating the relationships between normalized and raw biomarker concentrations among knees with effusion (undergoing a traditional aspiration) and without effusion (requiring a saline-assisted aspiration). Design: Validation study based on secondary analyses from 2 cohort studies. Setting: Outpatient orthopedic clinic and basic-science laboratory. Participants: Participants had moderate to severe radiographic knee osteoarthritis (n = 15 with and 11 without effusion) and no osteoarthritis or effusion (n = 4). Interventions: The same orthopedic surgeon performed all synovial-fluid joint aspirations, including saline-assisted aspirations. Main Outcome Measures: The authors used multiplex enzyme-linked immunosorbent assays to determine 7 synovial-fluid biomarker concentrations. They then calculated correlations between raw and normalized (to total synovial-fluid protein content) biomarker concentrations. Results: The authors excluded 1 sample collected with a saline-assisted aspiration because it contained blood. Normalized biomarker concentrations had positive associations with raw biomarker concentrations (r = .77-99), with the exception of interleukin-13 and interleukin-1Β among knees that underwent a saline-assisted aspiration. Excluding interleukin-1Β, associations between normalized and raw biomarker concentrations were consistent between knees that had a saline-assisted or traditional aspiration. Conclusions:Saline-assisted aspiration is a valid technique for assessing the local biochemical changes in knees without effusion.