Knee Recovery ReserachRebuilding Strength and Regaining Range of Motion

Full Knee Recovery in 10 weeks beginning 10 Months after Two Knee Arthroplasty Surgeries Using a Patented New Device: The Pressure Modulated Knee Rehabilitation Machine, X10

Dr. Marshall Allegra1


Dr. Carl Freeman2


Background: Kevin, our 58 year-old patient, had total knee arthroplasty on both knees. The first was a left knee partial knee replacement, August 11, 2013. Kevin had a right total knee arthroplasty on May 30, 2014 following an industrial accident at his job site, the Port Authority of New Jersey. His employer allowed him one year to recover and return to work. Subsequent to his surgery, in July of 2014 his physical therapist ripped his right quadriceps tendon while manipulating his leg causing Kevin to temporarily cease therapy – which resumed in October 2014. In February of 2015, Kevin had achieved 97 degrees range of motion, was not making significant gains and again had to cease therapy because of emergency stomach surgery. By mid-March 2015 he was once again ready to restart his physical therapy. However, with only 12 weeks remaining before he had to return to work, and his physician was ready to sign permanent disability papers, because of Kevin’s lack of progress. Kevin’s right leg had significant atrophy and he was unable to walk without a cane or walker. At this point, Kevin became aware of the newly patented Pressure Modulated Knee Rehabilitation Machine (PMKR), the X10 and contacted its manufacturer, Halley Orthopedics. Kevin began using the X10 on March 15, 2015, having only until May 30th to fully recover and return to work or lose his job. Ten weeks later Kevin reported to work with a full range of motion and able to walk (all day in construction shoes) the necessary 10,000 steps a day to do his job. Kevin succeeded in regaining range of motion and rebuilding strength after TKA.

Purpose: Here we describe how the PMKR X10 machine can be used to rapidly facilitate patient regain range of motion and rebuilding strength after TKA, even nine to ten months post-surgery with no manual physical therapy. We also illustrate the use of a Fitbit to assess daily patient progress.

Methods: Kevin was given an initial assessment consisting of: 1) measuring his range of motion, using the X10, 2) the Tinetti Performance Mobility Oriented Assessment (Tinetti et al., 1986), 3) the TUG test (Mathias et al. 1986, Podsiadlo and Richardson 1991), and 4 the WOMAC test (Quintana, et al., 2006 and Riddle et al., 2012) to assess his functional status).  Kevin used the X10 three times a day for thirty minutes each time. The X10’s onboard computer continually assessed and recorded his performance stroke by stroke, enabling Kevin to see his progress and to transmit data to his coach who monitored his progress.

Regaining Range of Motion and Rebuilding Strength After TKA

Results: In seven weeks of X10 use Kevin’s right leg ROM increased from 112° to 129° (he ultimately reached 130°). His left leg ROM increased by 14°.  The Tinetti, TUG and WOMAC were given on March 15th and May 15th.  The Tinetti went from 8/16 to 16/16, The TUG went from 25 seconds to 8 seconds and the WOMAC went from 80/96 to 46/96.  Kevin’s right quadriceps strength at 40° (for example) increased four-fold, and his right hamstring strength increased seven-fold. The Fitbit data showed that on March 15th Kevin was doing less than 100 steps a day and by May 15 he was doing over 11,000 steps a day. His sedentary time decreased by more than 300-400 minutes a day and his activity increased by a similar amount. By May 15, Kevin was burning more than 1000 additional calories a day, a 50% increase. Kevin’s pain had entirely ceased in both legs by April 29th and remained at 0 thereafter.

Conclusion: The use of the X10 enabled Kevin to recover his full range of motion in less than 10 weeks and become fully functional. He achieved this by using X10 two to three times a day for 30 minutes for range of motion, and every other day on the strengthening modules on the X10. Kevin used the X10 in his own home without direct supervision from a physical therapist. Moreover, the X10’s onboard computer continually assessed his performance stroke by stroke, enabling Kevin to see his progress and to record it and transmit it to his coach so that Kevin could be discharged from treatment based upon his performance and not the time spent in therapy. This data supports the conclusion that X10 can radically reduce the time needed for recovery from a TKA and allow patient discharge, not based upon the number of visits, but rather objective outcome measures. Accordingly, the X10 can usher in a new era both in cost savings and research.

The X10 Meta-Blog

We call it a “Meta-Blog” because we step back and give you a broad perspective on all aspects of knee health, surgery and recovery.

In this one-of-a-kind blog we gather together great thinkers, doers, writers related to Knee Surgery, Recovery, Preparation, Care, Success and Failure. Meet physical therapists, coaches, surgeons, patients, and as many smart people as we can gather to create useful articles for you. Whether you have a surgery upcoming, in the rear-view mirror, or just want to take care of your knees to avoid surgery, you should find some value here.

Subscribe to the Blog Here

* indicates required

  1. Metropolitan Surgical Institute, 540 Bordentown Ave, South Amboy, NJ 08879
  2. Carl Freeman, Department of Biological Sciences, Wayne State University, Detroit MI. 48202
Print Friendly, PDF & Email

Leave a Reply

Your email address will not be published. Required fields are marked *

Post comment