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      CMC Thumb Arthritis

      Osteoarthritis in the thumb is the most common form of arthritis affecting the hand. Women are more likely to be affected than men. Thumb arthritis is usually found at the carpometacarpal joint (CMC), located at the base of the thumb.

      Treatment of CMC thumb arthritis can be useful for non-surgical approach for patients with mild symptoms and for when surgical procedure is recommended. 

      Non-surgical treatment consists of splinting and intake of oral anti-inflammatories. The usage of an orthosis helps stabilize the joint to reduce pain, inflammation and swelling.  

      The H1 model is frequently used to treat CMC thumb arthritis. The H1 model (see picture) is next to our A1 model (wrist orthosis), one of the most designed models in the Spentys Application.  

      H1Schermafbeelding 2021-08-26 om 13.51.23Schermafbeelding 2021-08-26 om 13.51.39Schermafbeelding 2021-08-26 om 13.50.38

      At Spentys we provide two different versions of the H1 model.  

      • H1 (short version - not pictured): the part of the thumb will only integrate the thumb to the MCP joint.  
      • H1 (pictured): the immobilisation of the thumb will integrate the MCP joint. Only leaving the IP joint free to move. 

      Printer and materials 

      Depending on the severity of the osteoarthritis, the properties of the material will be different. 

      The following printing techniques and materials are the most used at Spentys. 

      • MJF - TPU: TPU is a flexible material and is best used in situations where the symptoms are mild. TPU will give enough support and immobilisation to reduce pain and decrease swelling. 
      • FDM - PP: PP has semi-flexible, fatigue-resistant, chemical-resistant and thermoformable properties. PP is also described as semi-rigid. The H1, printed in PP will be firm and less likely to deform, giving the hand full support and immobilisation. 

      A different printing technique that can be used to create a H1 model is FDM-TPU. FDM-TPU is a technique that can be put in between MJF-TPU and FDM-PP on the ‘rigidity-scale’. When creating a model in FDM-TPU don’t add alveoli, otherwise, the printing will fail. So, because of the solid form, the model will be more rigid in FDM-TPU than MJF-TPU. 

      Settings 

      We recommend the following settings when printing the H1 model. 

        Global thickness Offset Alveoli
      FDM-PP 3mm 1mm Yes
      MJF-TPU 4mm 1mm Yes