This week we have been reading an interesting journal in Osteoarthritis and Cartilage by Vafaeian et al, 2017. It is titled: Finite element analysis of mechanical behaviour of human dysplastic hip joints: a systematic review.
This systematic review highlights a few key facts:
- DDH is present in 1-3/1000 live births.
- DDH accounts for one-third of hip replacement surgeries in patients under 60 years old.
- DDH which is left untreated can lead to the following symptoms: mechanical instability, muscle imbalance, limited mobility, subluxation, abnormal joint loading which can cause increased cartilage shearing and development of osteoarthritis.
- The earlier DDH is addressed the less likely the joint is to degenerate and develop osteoarthritis.
- The labrum plays a key role in hip stability in the normal hip. In the dysplastic hip the mechanical contribution of the labrum has been found to be between 2-11 times greater.
- Therefore in dysplastic hips there is increased load and shearing forces on the labrum, which eventually results in anterosuperior tearing of the labrum. Labral symptoms can be one of the first issues that a patient experiences- which leads to a diagnosis of hip dysplasia.
- There is evidence of increased stress on the lateral acetabular roof, which is often where the first signs of osteoarthritis occur and sclerosis is often noted on x-ray.