Are we being too cautious with ‘new hips’

Hip replacement surgery (anterior hip arthroplasty) involves surgical access through the anterior hip capsule. After surgery, patients are typically moved to inpatient rehabilitation where they spend a considerable amount of time learning and practicing precautions to protect their new hip from dislocation. Recently, researchers from Marianjoy Rehabilitation Hospital in Wheaton, Ill. compared inpatient rehabilitation outcomes between patients who followed these precautions and those who did not.

"We noticed postoperative hip precautions were being dictated by the surgeon's preference rather than the operative technique," explains Noel Rao, MD, FAAPM; professor and chairman, Rosalind Franklin University of Medicine and Science, and former vice president of medical affairs and residency director at Marianjoy Rehabilitation Hospital, and lead investigator in the study. "Furthermore, surgeons using the same approach in the same surgical group varied on whether they placed patients under restrictions. Some did and some did not, which raised the question -- what would be the impact of not having restrictions on hip dislocation rates and length of stay using the anterior surgical method? If reduced restrictions do not increase hip dislocation rates and patients have a shorter length of stay, they could be rehabilitated and reintegrated into the community sooner."

Dr. Rao's team looked at the medical records of 68 people who underwent hip replacement surgery and noted each individual's functional independence measures (called FIM) at admission, daily during their stay and at discharge. FIM scores are often used by healthcare professionals to measure a person's overall ability to perform certain tasks (e.g., moving, walking, and self-care) independently. The researchers also noted each person's length of hospital stay and discharge disposition.

Thirty-one patients were admitted to inpatient rehabilitation without post-operative surgical precautions, and 37 were admitted with precautions. The two groups were very similar in age (around 67, on average), and both groups had similar FIM scores when admitted.

At the time of discharge, both groups had made similar progress in their overall FIM scores and their daily FIM improvements, but differed in length of hospital stay. The group who entered rehabilitation without post-operative precautions typically had a three-day shorter stay than those who observed precautions (nine days and 12 days, respectively). Ultimately, this translated to improved FIM efficiency for the group that did not observe precautions, and this group did significantly better in daily motor FIM and overall FIM gains.

"While both groups made similar overall progress during inpatient rehabilitation, the group that did not observe post-operative precautions made gains within a shorter timeframe as they did not have restrictions to follow and therefore did not have to spend time learning and consistently demonstrating hip precautions, which takes some time to accomplish," explains Dr. Rao of the findings. "The absence of restrictions allowed these patients to improve their FIM scores quicker resulting in a shorter length of hospital stay. Additionally, we anecdotally observed that reduced restrictions do not increase hip dislocation rates."

Based on this study, Dr. Rao suggests healthcare professionals should not be overly concerned about using hip precautions after anterior approach hip replacement surgery, if the operating surgeon has made a clinical determination that the patient doesn't need such precautions. Additionally, Dr. Rao suggests patients considering hip replacement should discuss their surgeon's preference for post-operative precautions and determine if they agree with their surgeon's method.

Regarding next steps, Dr. Rao explains, "With newer surgical techniques and improved expertise of surgeons, more patients are being discharged home directly following this procedure. This is more evident in patients not requiring hip precautions than in patients who have restrictions. If this trend continues, we may want to look at expanding our existing outpatient therapy programs to accommodate more of these patients."