Femoral Osteotomy FAQs
Femoral Osteotomy FAQs
Written By Dr Jason BROCKWELL
Last update: Aug 26th 2020
What is a Femoral Osteotomy?
The femur is the thigh bone. The term ‘osteotomy’ means ‘cutting a bone’. Femoral osteotomy is an operation to correct the anatomy by cutting the thigh bone and repositioning it.
If the acetabulum, or socket of the hip joint is also incorrectly angled or twisted, this would be cut and corrected at the same time [1], which is called a ‘pelvic osteotomy’. If the head of the femur (ball in the ball and socket of the hip joint) was ‘out-of-round’ this could also be corrected at same time by a ‘Heyman-type femoroplasty or some other procedure.
Who needs a Femoral Osteotomy?
If the thigh bone is the wrong shape, it can affect the hip or the knee, or both. Femoral (and tibial) osteotomy can be very helpful for correcting knee pain [2, 3], but these FAQs refer to the hip. Usually patients requiring a femoral osteotomy for hip problems will have hip or groin pain.
What can be the problem with the femur?
There are three common problems with the shape of the femur:
- it can have an incorrect amount of twist along its length (‘version’) and/or
- the neck-shaft angle can be wrong, and/or
- the femoral head can be the wrong shape
Natural History
The natural history depends on the type of problem and the severity of the problem: minor problems may be asymptomatic for life, whereas severe problems may result in hip arthritis in early adulthood.
Diagnosis
History:
The condition may be asymptomatic, or there may be pain, which may be specifically felt around the hip, or, more usually, will be non-specific, and may be felt in the groin, buttock, low back, thigh muscles or knee.
Examination:
The hip may be normal, or there may be pain especially with flexion, adduction & internal rotation of the hip. Often one’s feet point inwards or outwards when walking. The ranges of motion at the hip may be abnormal.
X-rays:
X-rays of the hips and pelvis are very helpful if they are done in the right way: it is usually necessary to take an X-ray of the whole pelvis, but they will not show version (twisting) accurately. I believe the most useful X-rays are “Supine AP pelvis & hips and modified frog laterals both hips”.
CT scan:
It is very useful for defining acetabular version and femoral version, which requires cuts to be made through the knee as well. CT provides very high definition images of the bone. It is possible to measure femoral version by specially taken plain X-rays, but more information is available with CT scanning.
MRI:
MRi is also able to measure the important angles on the bones, though it does not produce quite as high definition of the bone as CT scanning, but it is also helpful for ruling out other causes of hip pain, such as avascular necrosis (AVN) of the femoral head, infection, tumours and some other problems.
Principal Differential Diagnoses (ie ‘What else could it be?’)
- Arthritis of the hip – this problem is more common in Caucasians.
- Avascular necrosis (AVN) also known as ‘osteonecrosis’ of the femoral head (ONFH) – this problem is common in Asians.
- Other causes of hip pain, such as Femoro-Acetabular Impingement or acetabular dysplasia.
- Other causes of groin pain, such as a true hernia or ‘sports hernia’, pain from the back or SI joints, a ‘groin strain’ or adductor strain, osteitis pubis, a stress fracture, infection, tumour etc.
Treatment options
• No treatment: Avoid impact, wear soft soled shoes, control body weight, take glucosamine 1.5 grams per day long term, take painkillers as needed, have steroid injections into the hips as needed, and accept the possibility or likelihood – depending on the severity of the dysplasia - of progression to arthritis.
• Hip Arthroscopy (‘keyhole surgery’) to assess the joint prior to femoral osteotomy and to provide temporary relief by cleaning the joint a little. Arthroscopy cannot correct or cure incorrect alignment of the femur, but, if the problem is relatively mild, it may be sufficient to take away pain, and prevent the need for the more major procedure of femoral osteotomy.
• Femoral osteotomy to correct the anatomy. This is usually the best treatment, but if the X-ray or arthroscopy shows the joint is already badly damaged it is probably too late, and one would probably be best to go for hip replacement.
• Hip replacement or resurfacing. If the hip joint is arthritic, it is necessary to replace or resurface the joint. Sometimes it is necessary to combine a hip replacement or resurfacing with a femoral osteotomy, as the artificial joint will not work well if it is sitting in the wrong position because the femur is the wrong shape.
Types of Femoral Osteotomy
If the bone is simply twisted wrongly, a pure rotational femoral osteotomy is performed. In many cases this can be done by fixing the osteotomy with an ‘intramedullary nail’ – a metal rod which goes inside the bone, with very small incisions, and it is usually possible to put full weight through the leg immediately. If the neck-shaft angle is incorrect, it is usually necessary to use a plate and screws to hold the bone in the new position. This usually requires about a 15cm incision on the side of the thigh. It is not usually possible to put full weight through the plate, and it is necessary to walk with the aid of crutches until the osteotomy has healed, usually a minimum of 6 weeks.
References
- Vallamshetla, V.R., E. Mughal, and J.N. O’Hara, Congenital dislocation of the hip. A re-appraisal of the upper age limit fortreatment. J Bone Joint Surg Br, 2006. 88(8): p. 1076-81.
- Bruce, W.D. and P.M. Stevens, Surgical correction of miserable malalignment syndrome. J Pediatr Orthop, 2004. 24(4): p. 392-6.
- Dickschas, J., et al., Operative treatment of patellofemoral maltracking with torsional osteotomy. Arch Orthop Trauma Surg, 2011.
- Wiberg, G., The anatomy and roentgenographic appearance of a normal hip joint. Acta Chir Scand, 1939. 83(Suppl 58)(83(Suppl 58)): p. 7-38.
- McBryde, C.W., et al., Metal-on-metal hip resurfacing in developmental dysplasia: a case-control study. J Bone Joint Surg Br, 2008. 90(6): p. 708-14.
- Kumar, D., C.E. Bache, and J.N. O’Hara, Interlocking triple pelvic osteotomy in severe Legg-Calve-Perthes disease. J Pediatr Orthop, 2002. 22(4): p. 464-70.
Glossary
- Acetabulum: The socket of the hip joint in the pelvis.
- AVN: Avascular Necrosis of the femoral head. In this condition the blood supply to the femoral head is interrupted and the bone dies. Also known as ‘Osteonecrosis of the Femoral Head’ or ‘ONFH’.
- Cartilage: The smooth shock-absorbing material which covers the ends of the bones in a joint, forming the bearing surface.
- Dysplasia: Not properly formed.
- Femur: Thigh bone.
- Hip: The joint between the pelvis and the thigh bone ie between the body and the leg.
- Impingement: Pinching or jamming.
- Osteotomy: Cutting of a bone.
- Version: The degree of rotation or twist in the horizontal plane.