Age 55 used to be considered "too young" for a total hip replacement. Concerns about how long the implant would last, bone loss with future surgeries, and a high rate of complications often meant patients in pain just had to tough it out and wait. Now patients as young as 14 years old are having hip replacement surgery. The authors of this article give us an inside look at the challenges and complexities of total hip replacement in the very young patient.
Most of these surgeries are being done for young adults who have severe hip damage or deformity. Such significant changes to the hip are mostly caused by osteonecrosis (bone death), osteoarthritis (usually the result of a previous injury), or juvenile rheumatoid arthritis. The goals of surgery are to relieve pain, improve motion, and restore function.
One of the reasons total hip replacements are now possible in young adults has been the switch from cemented to noncemented implant (called component) parts. Cementless cups and heads means less bone is lost when removing the implants if and when they need to be redone after 10 or 15 years. Bone loss often means leg length shortening so this feature helps reduce leg length differences, too.
A second reason results are better these days making earlier hip replacement possible is the advancement of surgical techniques. Minimally invasive approaches, muscle preservation, imaging studies to help identify structural deformities also help produce improved outcomes.
But surgeons still face many challenges when working with this group of patients. They often have had previous surgeries. This can mean plenty of scar tissue to deal with, the presence of other hardware (pins, screws, metal plates), and severe muscle and joint contractures (stiffness). Careful evaluation and pre-operative planning is advised (more than is needed for older adults who just have degenerative osteoarthritic joint changes).
The surgeon must choose the best approach and implant possible for each patient. Sometimes this decision requires special imaging studies. Magnified X-rays, MRIs, and CT scans give the surgeon a three-dimensional (3-D) understanding of the joint angles, deformities, bone condition, and bone/joint size. Special thought and care goes into removal of previously used hardware before implanting the new hip joint.
All these decisions brings the surgeons back to the need to find better ways to treat young patients with hip conditions that might require early hip replacement. Joint-preserving techniques are being developed that help improve biomechanics of the diseased or deformed hip joints.
Special surgical techniques have been developed to address problems with impingement and subtle structural problems. The authors provide readers (especially other surgeons) details of these reconstructive surgical techniques. Attention is paid to the complexities involved with children needing surgery who have not reached full skeletal growth yet. Skeletal immaturity is a complex factor to be considered that isn't a part of hip joint replacement in older adults.
And the results? Well, all the data isn't in yet for long-term outcomes. Smaller studies reporting a series of patient outcomes have a wide variation in results as measured by implant loosening, number of revision surgeries required, and length of time between implantation and revision surgery. Patient symptoms (pain, stiffness) and function (ability to walk without a limp) are important measures. Patient satisfaction is another way to measure and report results.
The bottom-line is that studies so far conclude that a total hip replacement is an excellent treatment option even for young (very young!) patients. It does require quite a bit of preparation and pre-planning. The procedure can be very complicated because of the presence of deformities, structural or biomechanical problems, and even the effects of systemic diseases that cause these hip problems. But with today's more modern approaches, results are excellent. Patients can expect some bumps along the road due to the possibility of complications, which still remain high in many cases.
Reference: Gregory G. Polkowski, MD, et al. Total Hip Arthroplasty in the Very Young Patient. In Journal of the American Academy of Orthopaedic Surgeons. August 2012. Vol. 20. No. 8. Pp. 487-497.