Hip Joint Anatomy

One of the most important joints that hold the upper body weight is the joint of the hip. It is also one of the most complicated structures of the human body. The joint is consisted of a socket which holds a ball like structure in it which is movable and responsible for the hip movements in a human body. The hip joint is situated on the upper part of the femur which is also known as the femur head and at the acetabulum of the pelvis. The lower limbs that are the legs and the pelvic girdle are joined together with the help of this structure. Since, the hip joint carries the weight of the body, it is not very much movable. The joint is supported by various other structures and the stability of the joint thereby increases along with the supply-chain of the neurovascular system.




Muscle Movements of the Hip joint

There are different types of movements that the muscles do in the joint of the hip for the proper body movement and flexibility. They are in medical terms known as flexion, extension, abduction, rotation and many more. The level or degree of the flexion movement is based on the positioning of the hamstring and the knee in the human body as everybody is different. If you position your knee is flexed, then this movement can relax your hamstring muscle. Moreover, the flexion of the hip is also increased while in this position. The extension of the joint is controlled by the capsule which is there in the joint. There are other muscles which move when the hip moves to support it. Here is a detailed listing of the muscles which all take part in the different types of movements:

  1. Flexion: The muscles which help in this hip movement are iliopsoas, Sartorius and the rectus femoris.
  2. Extension: In this movement, the muscles which take part are gluteus minimus and medius, bicep femoris, semitendinosus etc.
  • Lateral rotation: The main muscles which help in this movement are Gluteus maximus, bicep femoris along with the deep gluteals.
  1. Abduction: The main muscle which helps in this hip movement of the joints is magnus and the brevis along with the adductors longus, gracilis and the pectineus.

Structure of the hip

The main structure of the hip divided into two parts which are:

  1. Articulating surface: The acetabulum and the femur head articulate at this place. The femur fits perfectly into the acetabulum due to the hemispheric shape of it. On the lateral side of the pelvis, the socket is there and there lies the cup like structure too. Articular cartilage then covers the whole of this structure to protect it from jerks and damage etc. Since, the cartilage has to bear the weight; it is thick at many places.
  2. Ligaments: The ligaments are the crucial part of the joint of the hip as it helps in the stability of the joint and helps in movements. It is further divided into two different categories which are as follows:
  • Extracapsular: These ligaments comes in the set of three which are
  • Iliofemoral: The location of this ligament is to the anterior part of the joint. This ligament is originated from the ilium which is commonly known as the hip bone and connects to the thigh bone. This ligament helps in controlling the hypertension of the hip joint and the bones and muscles.
  • Ischiofemoral: This ligament is situated on the posterior part of the body and mainly helps in controlling the level of extension that the femur can handle.
  • Pubofemoral: This ligament is there to handle excessive extension and abduction movement in the hip bone and the hip area.
  • Intracapsular: It is one ligament and not a set of ligaments which is situated at the femur head. It is comparatively a small one than the extra-capsular ligament. It is there to enclose the obturator artery branches.

Besides the above mentioned problem of the hip joint which needs to be treated with immediate effect, there are other problems in the hip area that one may face are dislocation of the head of the femur or the fracture of the femur neck and other.

Dr Dhananjay Gupta

Dr Dhananjay Gupta
Director and Senior Consultant,
Orthopaedics and Joint Reconstruction and Replacement Surgeon
Fortis Flt. Lt. Rajan Dhall Hospital, Vasant Kunj, Delhi.