Hi Inersha

In my experience hyperextension at the knees is usually coupled with increased lumbar lordosis, anteriorly tilted pelvis and reduced core stability. Correcting the pelvis to a neutral position will make it harder to hyperextend the knees and will improve whole body alignment. A feeling of instability is common when the body is held in this new posture but is overcome the more it is practiced and subsequently as greater control is gained .

People with hypermobility should refrain from taking their joints to the end of their range to reduce the risk of joint damage. The feedback systems within hypermobile joints can be less effective and the overstretching of joint structures may not be fedback to the client making the joint vulnerable to injury.

You cannot reduce the increased range at hypermobile joints but you can strengthen the muscles surrounding the joints to provide stability and to 'brace' the joint and thus increase the control. This means that the person can 'actively' work to maintain the joint in a neutral position and thus avoid over extending.

I would therefore recommend starting with postural correction, pilates based core stability exercises, and general strengthening exercises that do not take the joints beyond 'normal' and that are practiced with the body in alignment and the core 'switched on'.

Yes, hyperextension at the knee may predispose to shin splints as the direction of forces going through the foot and ankle complex are altered due to a more dorsiflexed ankle position. Over-pronation ( rolling in ) of the foot can also add to this.
Are you referring to Acute Compartment syndrome or chronic exertional (CECS)? My experience with this rather limited I'm afraid but I hope I've offered some help with your other quieries.