Dedicated to the acceptance, medical treatment, & legal protection of individuals in the process of correcting the misalignment of their anatomical sex, & supporting their transition into society.
Knee Replacement Surgery. The stresses and strains of everyday life take a toll on the altered anatomy of HBS patients, whether F2M or M2F. Limb and joint replacement, particularly as the HBS population ages, becomes a real possibility.
Osteoarthritis of the knee is a disease of age and the most common cause of disability in the USA. Women comprise 60 percent of the new cases.
In 2006, the US Food and Drug Administration (FDA) approved the first artificial knee designed and marketed specifically for women. However, the manufacturer only had to prove the new knee would not perform worse for women than the company's current products. No patient studies of the new knee were offered to the FDA. In any case, the approval raised questions for HBS.
The average knees of natal females and males can differ in several ways. As just one example, a woman's thigh bone where it meets the knee is narrower in women and also attaches to the shin bone at a different angle, due to a woman's wider hips. Some M2F patients had thin bones to start with while F2Ms may well have started that way.
The bodies of transitioning HBS patients undergo profound changes due to changes in musculature and bone density following hormone therapy (HT) and surgery. However, the professional literature on replacement surgery for patients born HBS is minimal.
TS-Si asked an FDA spokeperson for an update on our question in 2006: "Have medical studies focused on the HBS population?" Her answer was "Not that I know of."
The risks associated with limb and/or joint replacement can be significant if an HBS patient does not fully disclose her/his relevant medical history to physicians.
Newark, DE, USA. Osteoarthritis of the knee is a disease of age and the most common cause of disability in the USA. Women comprise 60 percent of the new cases. The stresses and strains of everyday life take a toll on the altered anatomy of HBS patients, whether F2M or M2F. Limb and joint replacement, particularly as the HBS population ages, becomes a real possibility. So, did you put new knees on your task list for the New Year?
New research indicates that women wait longer to pursue knee-replacement surgery than men do. By postponing surgery until they can no longer stand the pain, these women may also risk putting their mobility, and quality of life, on hold indefinitely, according to Lynn Snyder-Mackler, a professor at the University of Delaware (UD).
A Mechanical Theory for the Effectiveness of Bracing for Medial Compartment Osteoarthritis of the Knee. Dan K. Ramsey, Kristin Briem, Michael J. Axe, and Lynn Snyder-Mackler. J. Bone Joint Surg. Am., 2007;89:2398-2407. doi: 10.2106/JBJS.F.01136.
The research is one of two studies led by Snyder-Mackler and reported in the Journal of Bone and Joint Surgery (JBJS). “Doctors typically tell patients to wait to have knee replacements until they just can't stand the pain any longer,” Snyder-Mackler said. “Our research shows that's bad advice — and worse for women than it is for men — because your level of function going into surgery generally dictates your level of function after surgery,” she noted.
Lynn Snyder-Mackler (left), Distinguished Alumni Professor in the UD Department of Physical Therapy, tests the knee strength of Alice Voorhees, a patient at the Physical Therapy Clinic.
Photo by Kevin Quinlan
The UD Physical Therapy Clinic Laboratory which handles more than 300 visits by patients each week. The clinic evaluated 229 candidates for total knee replacements, including 95 men and 126 women with osteoarthritis, were evaluated and then compared to 44 healthy men and women who matched them in gender, age and body-mass index. Each subject took part in a series of standard physical tests such as stair climbing and the distance covered in a six-minute walk.
The quadriceps muscle is the major thigh muscle that extends and straightens the knee. The strength of the participants' quadriceps and range of knee motion also were assessed at the UD clinic.
“The women afflicted with osteoarthritis were at a much more advanced stage than the men with the disease,” Snyder-Mackler said. “The women all had painful end-stage osteoarthritis, where the cushion of cartilage padding the knee bones has completely deteriorated and you basically have bone hitting against bone.”
Why do women wait so long for surgery?
Snyder-Mackler says there may be a number of reasons. Perhaps women can bear pain better than men, or a woman's world increasingly revolves around the home as we age, or it could be that women are just trying to follow doctor's orders.
“Osteoarthritis of the knee is the most common cause of disability among Americans. It's a disease of age that affects more women than men on a 60-40 basis,” Snyder-Mackler said. “Physicians generally have advised patients to wait as long as they can before pursuing knee replacements, with the thinking that it is a once-in-a-lifetime surgery that should last an average of 20 years. "
She reiterated her earlier statement that, essentially, the patient's pre-operative condition influences the outcome. She added that "… delaying surgery can limit the quality of life of patients because how they function before surgery indicates their performance afterward.” Women need to become more educated about the risks and benefits of knee-replacement surgery, Snyder-Mackler said, and heed the warning signs of serious problems.
“When you feel profound buckling and weakness in your knee when climbing stairs, that is a major problem. You compensate — eventually, you may come downstairs only once a day,” Snyder-Mackler said. “As a result, you become sedentary and that's not good for your health. Earlier intervention can help preserve your mobility and quality of life.”
Snyder-Mackler says she has always been evidentiary research. “I've always had a burning desire to bring evidence to bear on clinical problems — that's always been really important to me,” Snyder-Mackler said. “There are real people at the end of the research loop — patients, physical therapists and physicians, and the patients' families.”
In a related study, Snyder-Mackler worked with Dan Ramsey, assistant professor of exercise and nutrition science at the University of Buffalo, and UD colleagues Kristin Briem, physical therapist, and Michael Axe, clinical professor of physical therapy, to determine the effectiveness of “unloader” knee braces in reducing pain and improving function in osteoarthritis patients.
The research showed that these braces actually promote pain relief by diminishing muscle contractions rather than by “unloading” or separating the joints. Such knee braces may provide an inexpensive treatment option for some osteoarthritis patients.
A. Additional information on the subject of replacement surgery is available at BoneSmart, a site operated by FARM Orthopedics, the Foundation for the Advancement in Research in Medicine.
B. Lynn Snyder-Mackler is a Distinguished Alumni Professor at the University of Delaware (UD), Department of Physical Therapy. She is a certified sports physical therapist and athletic trainer.
C. Snyder-Mackler led the research team for the study, which was funded by a grant from the National Institutes of Health. Her collaborators included Stephanie Petterson, who earned her doctorate in physical therapy and was a postdoctoral researcher at UD and is now a senior lecturer at the University of East London, and Drs. Leo Raisis and Alex Bodenstab, orthopedic surgeons at First State Orthopaedics in Newark, Del. Tracey Bryant contributed to this article.
A Mechanical Theory for the Effectiveness of Bracing for Medial Compartment Osteoarthritis of the Knee. Dan K. Ramsey, Kristin Briem, Michael J. Axe, and Lynn Snyder-Mackler. J. Bone Joint Surg. Am., 2007;89:2398-2407. doi: 10.2106 / JBJS.F.01136.
Abstract
Background. Evidence that knee braces used for the treatment of osteoarthritis mediate pain relief and improve function by unloading the joint (increasing the joint separation) remains inconclusive. Alternatively, valgus-producing braces may mediate pain relief by mechanically stabilizing the joint and reducing muscle cocontractions and joint compression. In this study, therefore, we sought to examine the degree to which so-called unloader braces control knee instability and influence muscle cocontractions during gait.
Methods. Sixteen subjects with radiographic evidence of knee malalignment and medial compartment osteoarthritis were recruited and fitted with a custom Generation II Unloader brace. Gait analysis was performed without use of the brace and with the brace in neutral alignment and in 4° of valgus alignment. A two-week washout period separated the brace conditions. Muscle cocontraction indices were derived for agonist and antagonist muscle pairings. Pain, instability, and functional status were obtained with use of self-reported questionnaires, and the results were compared.
Results. The scores for pain, function, and stability were worst when the knee was unsupported (the baseline and washout conditions). At baseline, nine of the sixteen patients reported knee instability and five of the nine complained that it affected their activities of daily living. Poor knee stability was found to be correlated with low ratings for the activities of daily living, quality of life, and global knee function and with increased pain and symptoms. Knee function and stability scored best with the brace in the neutral setting compared with the brace in the valgus setting. The cocontraction of the vastus lateralis-lateral hamstrings was significantly reduced from baseline in both the neutral (p = 0.014) and valgus conditions (p = 0.023), and the cocontraction of the vastus medialis-medial hamstrings was significantly reduced with the valgus setting (p = 0.068), as a result of bracing. Patients with greater varus alignment had greater decreases in vastus lateralis-lateral hamstring muscle cocontraction.
Conclusions. When knees with medial compartment osteoarthritis are braced, neutral alignment performs as well as or better than valgus alignment in reducing pain, disability, muscle cocontraction, and knee adduction excursions. Pain relief may result from diminished muscle cocontractions rather than from so-called medial compartment unloading.
Disease-Specific Gender Differences Among Total Knee Arthroplasty Candidates. S.C. Petterson, L. Raisis, A. Bodenstab, and L. Snyder-Mackler. J. Bone Joint Surg. Am., 2007; 89: 2327 - 2333. doi: 10.2106 / JBJS.F.01144.
Abstract
Background. Women with knee osteoarthritis are less likely to undergo joint replacement despite greater self-reported disability. The primary aim of the present study was to assess gender differences in the type and magnitude of osteoarthritis-related impairment prior to knee arthroplasty.
Methods. Two hundred and twenty-one knee arthroplasty candidates (ninety-five men and 126 women) and forty-four healthy gender, age, and body mass index-matched individuals were tested. Individuals with contralateral limb injury or abnormality, cardiovascular disease, neurological impairment, and medical conditions limiting activity were excluded. Collected data included Medical Outcomes Study Short Form-36 mental and physical component scores, the Knee Outcome Survey Activities of Daily Living Scale score, knee range of motion, timed up-and-go test time, stair-climb test time, six-minute walk distance, normalized quadriceps strength, and volitional muscle activation.
Results. Women in the arthroplasty group had lower Short Form-36 and Knee Outcome Survey scores, longer timed up-and-go test and stair-climb test times, shorter six-minute walk distances, and lower normalized quadriceps strength compared with men. Healthy women had longer stair-climb test times and shorter six-minute walk distances in comparison with healthy men. Between-group comparisons revealed that women in both the control group and the arthroplasty group had reduced normalized quadriceps strength in comparison with men, that healthy women had higher voluntary muscle activation in comparison with healthy men, and that female arthroplasty candidates had lower activation levels in comparison with male candidates.
Conclusions. Observed gender differences in strength and function appear to be inherent but are magnified in arthroplasty candidates. Strength and functional decline should be closely monitored in women with knee osteoarthritis to serve as an indicator of worsening condition, and preoperative interventions should reflect these gender-specific impairments.
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