Muscle mass, muscle strength, functional performance, and physical impairment in women with the hypermobility type of Ehlers‐Danlos syndrome – Rombaut – 2012 – Arthritis Care & Research – Wiley Online Library
Objective: To investigate
- lower extremity muscle mass,
- muscle strength,
- functional performance, and
- physical impairment
in women with the Ehlers‐Danlos syndrome hypermobility type (EDS‐HT).
This is exactly what I’ve been searching for: a study on muscle problems in EDS. Finally, I found some explanation of all the odd issues I’ve had with my muscles over the years.
Forty‐three women with EDS‐HT and 43 sex‐ and age‐matched healthy control subjects participated.
- Muscle mass was determined by dual x‐ray absorptiometry.
- Muscle strength and muscle strength endurance were measured with isokinetic dynamometry at angular velocities of 60, 180, and 240°/second.
- Static muscle endurance during posture maintenance was also assessed.
- Pain and fatigue were simultaneously evaluated by visual analog scale and the Borg scale, respectively. In addition, the chair rise test for assessment of functional performance and the Arthritis Impact Measurement Scales (AIMS) for physical impairment evaluation were used.
Compared to control subjects, EDS‐HT patients showed
- substantial lower extremity muscle weakness, reflected by significantly reduced knee extensor and flexor muscle strength and endurance parameters, with differences ranging from −30% to −49%;
- reduced static muscle endurance time; and
- diminished functional performance.
Lower extremity muscle mass was similar in both groups and unlikely to affect the muscle strength results.
By contrast, pain and fatigue were omnipresent and increased remarkably due to the tests [for EDS-HT patients]. Furthermore, the EDS‐HT group was physically impaired, especially in the AIMS domain walking and bending.
This study demonstrates severely reduced quantitative muscle function and impairment in physical function in patients with EDS‐HT compared to age‐ and sex‐matched controls.
The muscle weakness may be due to muscle dysfunction rather than reduced muscle mass. Whether muscle strength and endurance can be improved by appropriate exercise programs needs evaluation in further studies.
The above is only the abstract. I’ve clipped excerpts from the lengthy free full-text article below:
Muscle symptoms in EDS have long been considered to result from reduced physical activity (PA),
This is a perfect example of extreme prejudice against pain patients.
A woman complains about muscle pain to her doctor. He runs his standard repertoire of tests and trials for patients who present with muscle pain, but can’t find anything wrong.
When he can’t find the source of her pain or even verify its existence, he either assumes the pain isn’t real (in her head) and/or that it’s somehow her own fault, because she’s too lazy to “take better care of herself.”
And when we are overweight such conclusions are even more common; our weight and inability to lose it become the doctor’s sole focus. He already “knows” our pain is not serious – after all, he can detect nothing broken – and from then on merely tries to placate the patient or “get rid of” them.
I expect this is where most pain patients end up: trying to get help with pain (which is probably inexorably increasing) from someone who doesn’t believe they really have it.
Muscle symptoms in EDS have long been considered to result from reduced physical activity (PA), which may occur as a consequence of exercise avoidance due to joint hypermobility, joint instability, and pain.
However, recent studies have shown that primary muscle involvement in EDS can be expected based on altered interactions between muscle cells and extracellular matrix (ECM) molecules, of which collagen is an important component
Nevertheless, investigation of muscle performance in EDS‐HT is particularly important to gain a better understanding of how and to what extent muscle function is impaired in EDS‐HT. This knowledge may contribute to better management for these patients, which is currently poorly addressed
Therefore, we performed an extensive clinical study on lower extremity muscle function in EDS‐HT.
The primary objective was to investigate quadriceps and hamstrings
- muscle strength,
- strength endurance,
- functional performance, and
- muscle mass, as well as
- pain and fatigue associated with muscle strength tests,
in patients with EDS‐HT compared to healthy matched control subjects.
The secondary objective was to examine the extent of physical impairment in patients with EDS‐HT.
Significance & Innovations
- Patients with Ehlers‐Danlos syndrome hypermobility type (EDS‐HT) show considerably reduced lower extremity muscle strength and muscle strength endurance, which is reflected in a poorer functional performance.
- The muscle weakness may be due to muscle dysfunction rather than reduced muscle mass.
- Exercise‐induced pain and fatigue in patients with EDS‐HT increase disproportionately compared to the muscle performance, and remain extremely high and long‐lasting after the effort.
- Patients with EDS‐HT show important impairments in physical function, particularly in activities such as walking and bending.
The results of the muscle strength tests are shown in Table 2.
This table doesn’t format well enough to copy, but you can find it directly at the link.
The knee extensor and flexor maximal muscle strength (PT) was significantly lower in the patient group than in the control group at the angular velocity of 60°/second (P < 0.001) as well as at 180°/second (P < 0.001).
The results were even more marked when normalized for body weight (PT/BW), with differences ranging from −33.3% to −42.9%.
Reductions were approximately similar for knee extensors and knee flexors.
Muscle strength endurance
Seven EDS‐HT patients and none of the control subjects were unable to complete the isokinetic endurance protocol.
The results in Table 3 indicated that the EDS‐HT patients had significantly reduced isokinetic muscle strength endurance, as expressed by lower total work, and lower work during the first third and last third of the test duration compared to the control subjects, with differences ranging from −30.5% to −49.3%.
Furthermore, static muscle endurance was also markedly reduced in the EDS‐HT group as compared to the control group.
Actually, the EDS‐HT patients could not maintain both postures for even half the time of the control subjects.
Pain and fatigue
The results of pain and fatigue associated with the muscle strength and muscle strength endurance tests are shown in Figure 1.
Concerning pain severity, the EDS‐HT group generally reported mild lower extremity pain at rest just before the test. Immediately after the test, the median pain score increased to 40–60 of 100, which reflects moderate pain due to the test. One minute after the test, pain was only slightly reduced, with 10–20 mm on the VAS.
In contrast, the control subjects were pain free at every point in time.
Concerning fatigue, the patient group showed a greater level of fatigue than the control group at every moment.
In particular, the EDS‐HT group already showed some fatigue at baseline, in contrast to the nonfatigued control group. Immediately after the endurance test, EDS‐HT patients were completely exhausted, whereas the control subjects showed only a moderate fatigue. Finally, 1 minute after the test, EDS‐HT patients remained exhausted, whereas control subjects quickly recovered.
Furthermore, it was striking that the pretest Borg scores in the EDS‐HT patient group increased as the protocol moved on.
This indicates our muscles don’t recover as they should. Even after a rest, every additional effort merely adds to the fatigue instead of “starting over” like normal people do.
The EDS‐HT subjects showed significantly poorer lower body performance than the control subjects, reflected by an increased total time to complete 5 repeated stands from the chair (P < 0.001) and an increased average time per stand (P < 0.001) (Table 4).
The mean ± SD time of 2.3 ± 0.96 seconds in the patient group also suggested a slightly increased risk of falling in these patients.
The mean ± SD overall physical dimension scores were 3.4 ± 1.4 in the EDS‐HT group and 0.2 ± 0.2 in the control group (P < 0.001).
As shown in Figure 2, all subscale physical impairment scores were significantly higher in the EDS‐HT group compared to the control group, which indicated poorer physical function in the patient group.
The greatest physical impairment was observed in walking and bending and the least physical impairment was observed in self‐care activities.
…to be continued in tomorrow’s post.