The Apple Watch 4, with a large slate of health care apps either launched or in the works, presents an interesting new way to mesh technology with the delivery of primary care and outpatient services. Making moves to break into the $3 trillion U.S. health care industry, Apple has outfitted its latest iteration of the Apple Watch with an array of health technology that can monitor and collect health data ranging from pulse to physical activity to whether or not you’ve fallen and have trouble getting up.

While it won’t be able to treat any diseases or conditions any time soon, Apple Watch health monitoring can track day-to-day health of patients and potentially catch diseases and complications before they become life-threatening. One area where Apple hopes to make a breakthrough is postoperative recovery for patients undergoing major surgeries such as knee and hip replacements.

More than one million Americans undergo surgery for a knee or hip replacement every year. As that number grows, it’s more and more critical that health providers find new ways to limit and reduce the potential for life-threatening complications.

Surgeons with the American College of Surgeons found that postoperative complications posed the greatest risk for 30-day hospital readmissions for patients. Patients who developed postoperative complications had as much as four times higher risk of hospital readmissions compared to those who didn’t, and median hospital stays increased to 24 days from patients with three or more complications compared to nine days for those with one complication, and five days for those with none.

A study from the Journal of the American Medical Association (JAMA) found that when using a risk scoring system to predict failure to rescue (i.e. death from postoperative complications), 90% of postoperative deaths occurred in the highest risk bracket, most of whom died within a week of developing an initial postoperative condition. The study concluded that early intervention for high-risk patients who develop a postoperative condition presents the best way to prevent patient deaths.

What these studies mean is that if the Apple Watch 4 can successfully monitor postoperative patients for potential complications, and notify relevant health providers in a timely manner, the Apple Watch could potentially help save thousands of lives.

Apple partnered with Zimmer Biomet, one of the largest manufacturers of hip and knee replacement parts, to create an app called mymobility to help patients navigate the postoperative recovery period and keep on track with rehabilitation routines.

Apple is also working with Zimmer Biomet to conduct a large-scale study of postoperative knee and hip replacement patients using the Apple Watch and mymobility to analyze the effectiveness of the technology to catch postoperative complications and help with rehabilitation.

While the Apple Watch 4 is equipped with an FDA-approved EKG sensor to help monitor heart electrical activity, many of its other functions are still under longer clinical reviews.

Apple has yet to make significant progress on its partnership study with Zimmer Biomet on postoperative knee and hip replacement patients. Apple’s other long-term clinical study, Stanford Medicine’s Apple Heart Study, was started in 2017 and is slated to finish sometime in 2019.

So far, only two of the Apple Watch’s purported health monitoring innovations have had preliminary studies and initial FDA approval. Atrial fibrillation, an irregular heart rate that often signals a high risk of heart failure and stroke, was Apple’s first topic of study. This first preliminary study looked at 588 patients, half with atrial fibrillation and half without, and Apple found that the Apple Watch could read 90% of recordings, and of that 90% it could recognize 98% of patients with atrial fibrillation and 99% of patients without. The second preliminary study was early data from its Stanford Apple Heart Study. Stanford compared a traditional heart monitor to the Apple Watch, and they found that the traditional monitor successfully identified only 41% of patients with atrial fibrillation compared to 79% for the Apple Watch.

Apple hopes to eventually roll out other features such as a blood oxygen level sensor, respiration rate monitoring, and even a Parkinson’s Disease diagnosing app, but many of these features still require development and FDA approval.

The Apple Watch 4 has easily become one of the most promising pieces of technology available to consumers for new developments in primary care and outpatient services. However, many of its health functions as related to clinical practice are still under study, and several of Apple’s promised health apps are still under development.

The Apple Watch also remains prohibitively expensive for the majority of consumers, starting at $399 and rocketing up to as high as $799 for its top of the line model. Its extremely unlikely that health insurance companies would be willing to fork over funds to pay for or heavily subsidize expensive Apple Watches any time soon.

As Apple continues to dive headfirst into the health care industry, producing disruptive innovations that fit into a watch, we’ll see greater potential to connect the daily lives of patients to their primary care providers and postoperative health teams. But until Apple concludes its studies and finds statistically significant results, and finds a way to drastically make its technology more affordable, the Apple Watch 4 will remain just a far-off possibility for most patients.