Hip precautions were written to prevent dislocation, and the trials that tested them found little difference.

What the traditional precautions are, and why they exist

Hip precautions were created to reduce the theoretical risk of early dislocation while the soft tissue around the hip heals ¹. Dislocation means the ball coming out of the socket. Precautions are typically prescribed for at least six weeks, or until that tissue has at least partly healed ¹. AAOS OrthoInfo describes the same window: special precautions when sitting, bending, or sleeping, usually for the first six weeks ².

The classic posterior-approach list has three parts: no bending the hip beyond 90°, no bringing the leg across the midline, and no twisting the leg inward ¹. A 2020 systematic review describes the same three, with some protocols adding rules on sleeping position, pillows, and driving ³. In OrthoInfo's patient version: do not cross the legs at the knees for six to eight weeks, do not lift the operated knee higher than the hip, and do not lean forward or bend at the waist beyond 90° ⁴.

The precautions differ by surgical approach

The positions to avoid depend on where the surgeon entered the hip. After a posterior approach, the risky movements are flexion, adduction, and internal rotation ¹. After an anterior approach, the positions of concern are the opposite: extension and external rotation ¹.

Practice varies widely. In a 2018 survey, 44% of surgeons prescribed precautions to every patient, and about a third never did ¹. The list that applies is the one your surgeon wrote.

What the trials found when precautions were dropped

This has been tested. A 2020 systematic review pooled seven studies with 6,900 posterior-approach patients, 3,517 with precautions and 3,383 without. Dislocation occurred in 2.2% with precautions and 2.0% without, a difference that was not statistically significant ³.

A 2023 meta-analysis of 8,835 patients, including four randomised trials, reached the same place. In the trials, early dislocation occurred in 1.2% with precautions and 0.6% without, with a confidence interval that included an effect in either direction. Precautions made negligible or no difference to patient-reported function or to time back at work ⁵. The authors concluded that current evidence does not support routinely prescribing precautions after posterior-approach surgery, while rating that evidence as low to very low certainty ⁵.

Two cautions belong beside that. The pooled patients had a posterior approach for primary osteoarthritis, so the finding says nothing about revision surgery or other risk factors ⁵. And the risk of dislocation, though uncommon, is greatest in the first few months while tissues heal ².

Activity return, in general terms

The reviews above are about positions. On activity, the published pattern is this:

• Walking: OrthoInfo's guidance is to walk as much as you would like. It describes swimming as an excellent low-impact activity ⁴.
• Side sleeping: depending on the surgery, the surgeon may ask you to avoid certain sleeping positions or to use a pillow between the legs for a period ⁴.
• Driving: across 14 studies, the mean recommended return was 4.5 weeks, and brake reaction time was back to baseline at six weeks. The authors advise individual advice based on transmission, operated side, medication, and other conditions ⁶. OrthoInfo adds that driving waits until a patient is off opioid pain medication with strength and reflexes returned ⁴.
• Golf: OrthoInfo groups golf with bicycling and doubles tennis as lower-stress activities ⁴. A 2024 systematic review reported golfers returning to the sport, with 67% of patients back to sport within three months and most within six ⁷.
• Higher-impact sport: singles tennis, jogging, racquetball, basketball, and skiing put more stress on the joint ⁴. Surgeons disagree here. In one survey 51.5% permitted high-impact sport, and basketball, soccer, and skiing were frequently advised against ⁷. Most studies in that review found similar or better implant survival in active patients; one older study with earlier polyethylene showed more wear ⁷.

A golf swing rotates through the hip, and rotation is among the movements the posterior precautions limit ¹. When the swing is cleared is a decision for your surgeon from your exam and imaging.

When to call your surgical team

A prosthetic hip usually dislocates with a minor mechanism: a fall, bending to tie a shoe, standing from a low chair, or crossing the legs ⁸. After a posterior dislocation the leg looks shortened, bent, and turned inward, and the person cannot bear weight on it ⁸.

• Sudden severe hip pain with an inability to bear weight, or a leg that suddenly looks shorter or turned in or out. This needs emergency assessment ⁸.
• Fever above 100°F, chills, increasing redness, tenderness or swelling at the wound, drainage, or hip pain that increases both with activity and at rest. AAOS lists these as possible signs of infection ².
• Calf pain unrelated to the incision, calf tenderness, redness or swelling, or sudden shortness of breath or chest pain. These are listed as possible signs of a blood clot ².

Before leaving hospital, ask which approach was used, which positions are restricted and for how long, and the plan for side sleeping, driving, and any sport you play. Your surgeon decides each from your exam, imaging, and history.