Hypermobility spectrum disorder (HSD), related to earlier diagnoses such as hypermobility syndrome (HMS), and joint hypermobility syndrome (JHS) is a heritable connective tissue disorder that affects joints and ligaments. Different forms and sub-types have been distinguished, but it does not include asymptomatic joint hypermobility, sometimes known as double-jointedness. Symptoms can include the inability to walk properly or for long distances, and pain in affected areas. Some people with HSD have hypersensitive nerves and a weaker immune system. It can also cause severe fatigue and some cases cause depressive episodes. It is somewhat similar to other genetic connective tissue disorders such as Ehlers–Danlos syndromes. There is a strong association between HSD and neurodevelopmental disorders such as ADHD (Attention deficit hyperactivity disorder) and ASD (autism spectrum disorder). Classification
Hypermobility spectrum disorders are diagnosed when individuals have symptomatic joint hypermobility but do not meet the criteria for other connective tissue disorders, such as Ehlers-Danlos syndrome.The term "hypermobility spectrum disorder" was coined in 2017 after criteria for hypermobile Ehlers-Danlos syndrome were made more restrictive. In part, this classification change was designed to address the overlap between joint hypermobility syndrome and what was then known as Ehlers-Danlos syndrome, hypermobility type (EDS-HT), which some researchers believed were the same condition.
In a study conducted by Sjaastad, heating a patients body will cause the painful side of the forehead to sweat more in CPH patients, while there will be less sweating on that side for those suffering from cluster headaches. Treatments
A ten-patient study conducted by Pareja et al. found that all patients diagnosed with CPH were responsive to indomethacin and were able to completely control their symptoms. Doses of the drug ranged from 25 mg per day to 150 mg per day with a median dose of 75 mg per 24-hour period. Almost all cases of CPH respond positively and effectively to indometacin, but as much as 25 percent of patients discontinued use of the drug due to adverse side effects, namely complications in the gastrointestinal tract. According to a case study by Milanlioglu et al., 100mg of lamotrigine, an antiepileptic drug, administered twice daily alleviated all painful symptoms. No side effects were noted after two months of treatment. Dosage of lamotrigine was decreased to 50mg a day after the first two months, and no symptoms or side-effects were recorded after a three-month followup.Use of topiramate has also been found to be an effective treatment for CPH, but cluster headache medications have been found to have little effect. Epidemiology
Although CPH is often compared to cluster headaches, it is much less prevalent, occurring in only 1–3% of those who experience cluster headaches. CPH occurs roughly in 1 in 50,000 people, while cluster headaches are comparatively more common and are found in 1 in 1000 people.