Hi Insomnia and welcome to the Mattress Underground 
A mattress is one of the most subjective purchases you will make; as all sleepers are unique, so too will any consumers’ choice in mattresses be, based on you and your wife’s Stats (height, BMI, sleeping position(s) and any underlying health conditions) and PPP (Posture and alignment, Pressure relief, and Personal preferences). Depending on your type of injury, some mattresses may prove more comfortable than others.
A few resources you can review to get started on your search are the Mattress Shopping Tutorial to see how to find a great retailer or manufacturer, and the Mattress Specifications You Need To Know and the Mattress Durability Guidelines; this will tell you what specifications you should look for in any hood mattress, and how long various mattress materials will last over time.
Since you don’t have a particular mattress type in mind, if at all possible, you and your wife should set aside some time to try mattresses at a local showroom, just to see how they feel for you both. Latex has a particular feel, and is extremely durable, but some consumers don’t enjoy the feeling…testing out various latex firmnesses, and a latex hybrid (as innersprings also are popular with some, but not all sleepers) An innerspring support can provide the ‘edge support’ you seek - but you should look to find a sleep solution that’s both comfortable as well as supportive enough (especially if you are higher BMIs and/or have health conditions which affect your sleep). By making a ‘short list’ of mattress types you both like, you’ll be better equipped to assess specific mattresses whether online or at local retailers or manufacturers. If you have questions on any specific mattresses and provide your Stats, we may be able to comment on the suitability for you and your wife’s support and comfort needs.
~ Basilio