activities of daily living, referred to as the Palm Beach Spine Index (PBSI) . ... all tests: TW time improved from 351.40 seconds preoperatively to 449.19 seconds at 30 days (27.8%) ... been widely reported.1,2 Instead, more common are tests of.
THE PALM BEACH SPINE INDEX : A FUNCTIONAL MEASURE OF POSTLAMINECTOMY PATIENTS STEWART G . EIDELSON, MD, MICHAEL WHITEHURST, EdD, and LEE E . BROWN, MEd
The functional importance of spinal surgery has recently been investigated using a battery of tests, resembling activities of daily living, referred to as the Palm Beach Spine Index (PBSI) . Forty-two patients (23 men and 19 women, aged 74.2 ± 5 .7 years), with a primary diagnosis of moderate to severe degenerative spinal stenosis, underwent a series of functional tests before and after surgical intervention . The functional tests included a timed progressive treadmill walk (TW) at 1 .0 mph with a 0.4 increase in speed every 2 minutes for a maximum time of 10 minutes ; a chair stand test (CS), which required the patient to rise from a straight-back chair to a standing position as quickly as possible without the use of the arms ; and a timed weight-carrying task (WC) that involved having the patient walk a distance of 20 meters as quickly as possible while carrying dumbbells representing 10% of their body weight . Significant (P < 0.05) improvements were observed from preoperative to 30 days and 6 months postoperatively for all tests : TW time improved from 351 .40 seconds preoperatively to 449 .19 seconds at 30 days (27 .8%) and to 600.00 seconds at 6 months (33.5%), whereas the CS time improved from 0 .82 milliseconds to 0 .62 at 30 days (32 .2%) and 0 .35 at 6 months (77.1%), with WC time improving from 12.12 seconds to 9 .34 seconds at 30 days (29 .7%) and 6 .55 at 6 months (42.6%) . The functional improvements as surgical outcomes were successfully measured using the PBSI . Moreover, the results associated with the PBSI are easily understood by the patient and serve to facilitate selfmonitoring and adherence to postoperative treatment. Self-reports of pain and a loss of mobility in conjunction with radiographic analysis are not enough to maintain the support of managed care for both surgical and postsurgical care . In contrast, the PBSI serves as an alternative to subjective assessments (eg, pain) with a quantitative approach to recognizing the benefits of surgical intervention .
KEYWORDS : laminectomy, functional activities, spinal stenosis, mobility
Standardized testing of functional decrements or postoperative improvements relating to spinal surgery have not 1,2 been widely reported . Instead, more common are tests of mobility subjective measures of pain, and radiographic evaluations . 3-8 Although helpful, these tests and measures have limitations, including cost, time, and standardization . Recent attempts by managed care to contain costs have shown a need for a more objective and cost-effective means of measuring patient limitations and surgical outcomes . 9 That is, managed care is less and less supportive of tests that are not cost and time effective in identifying spinal problems and postoperative improvement . To that end, the Palm Beach Spine Index (PBSI) was developed . The PBSI is cost and time effective, reliable, and accommodates the patient in that the index is composed of functional tasks that are required of the patient in daily living . The PBSI includes a treadmill walk test, weight-carry test, and chair stand test . The functional nature of the PBSI offers a simplistic, affordable, and objective means of responding to cost-containment initiatives from managed care . The
From the Palm Beach Orthopaedic and Spinal Research Foundation, Boynton Beach, FL. Address reprint requests to Stewart G . Eidelson, MD, Palm Beach Orthopaedic and Spinal Research Foundation, 2828 South Seacrest Blvd, Suite 207, Boynton Beach, FL 33435 . Copyright © 1997 by W.B. Saunders Company 1048-6666/97/0701-0013$05 .00/0
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purpose of this investigation was to determine the efficacy of this outcome tool on postlaminectomy spine patients .
MATERIALS AND METHODS Forty-two consecutive patients (23 men and 19 women, average age 74 .2 ± 5 .7 years) who were diagnosed with degenerative spinal stenosis volunteered to participate in a pilot investigation designed to measure objective surgical outcomes . Surgical procedures included spinal decompression with single laminectomies at the L3-4: level and at the L4-5 level while multiple laminectomies were also performed at levels L3-5 and at levels L2-5 . The outcome measures used in this study, comprised the PBSI including a treadmill walk (TW), chair stand maneuver (CS), and weight-carrying task (WC) . These tasks were easily administered in approximately 20 to 30 minutes to patients before surgery, 30 days and 6 months postsurgery in a physical therapy environment . The TW test required each subject to walk at zero grade at a treadmill speed of 1 .0 mph with 0 .4-mph increases in speed every 2 minutes for a maximum of 10 minutes and a maximum speed of 2.6 mph (Fig 1) . The test was terminated before 10 minutes if the subject was unable to continue secondary to low back pain, leg pain, or fatigue. One trial was performed, and total time walking on the treadmill was recorded to the nearest second . The WC test required each subject to carry two weighted
Operative Techniques in Orthopaedics, Vol 7, No 1 (January), 1997 : pp 68-70
Fig 1 .-Treadmill walk test.
Fig 2.-Weight carry test.
dumbbells, one in each hand, a distance of 20 meters (Fig 2) . The total weight, representing 10% of the subject's body weight, was equally divided between each hand . When hearing the command "GO," the subject walked 20 meters as quickly as possible . One trial was performed, and time to complete the 20 meters was recorded to the nearest 100th of a second . The CS test required each subject to rise from a straightback chair to a standing position as quickly as possible without the use of the arms (Fig 3) . A spring-lever switch was secured to the lower portion of the chair and was compressed by the subject's lower back when assuming the seated position . A lead wire from the switch was connected to a clock timer . When hearing the command "GO," the subject stood, which opened the switch and thereby started the clock . As the subject stood, his or her head and shoulders interrupted a light beam emitted by a photocell and reflector, which were positioned just in front of the chair and supported by tripods on either side of the chair at approximately 4 feet . A lead wire from the light beam was also connected to the clock timer . Interruption of the light beam resulted in stopping the clock timer . Three trials were performed, and time to stand was recorded to the nearest 100th of a second .
were observed between preoperative and 30 days and preoperative and 6 months for all tests . The TW time improved 27.8% at 30 days and 33 .5% at 6 months . The CS time improved 32 .2% at 30 days and 77 .1% at 6 months,
RESULTS Results for each test preoperatively, at 30 days, and at 6 months are shown in Table 1 . Significant improvements PALM BEACH SPINE INDEX
Fig 3 .-Chair stand test .
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TABLE 1 . Results of the Mean Time for Each Functional Test TW (s) 351 .40 449 .19 600 .00*t
Preoperative 30 Days 6 Mo
CS (ms)
WC (s)
0 .82 0 .62* 0 .35*
12 .12 9 .34* 6 .55*
*Significantly (P < .05) different from preoperative test. tSignificanlty (P < .05) different from 30-day test . Abbreviations : TW, treadmill walk test ; CS, chair stand test ; WC, weight carry test .
and the WC time improved 29 .7% at 30 days and 42.6% at 6 months (Fig 4) .
DISCUSSION The tasks selected for this index were seen as important objective measures of functionality and true indicators of surgical outcomes . That is, engaging in a sustained walk, carrying objects, and rising from a chair without assistance would appear to be fundamental and requisite to independent living . 10 Similarly, the results associated with the PBSI are easily understood by the patient and serve to facilitate self-monitoring and adherence to postsurgical treatment . By using the PBSI instrument to measure postlaminectomy patients, we were able to chart their clinical progress . As seen in Figure 4, 30-day testing showed an average 29 .9% improvement in each task, which progressed to 51 .1% at 6 months . Therefore, the PBSI offers the physician an objective means of evaluating the patients' progress after surgery . Because of the cumbersome nature of subjective data collection tools, many spinal surgeons are not recording postsurgical outcomes . Self-reports of pain and a loss of functional ability in conjunction with radiographic analysis are not enough to maintain managed care support for both surgery and postsurgical care ."- " In contrast, the PBSI serves to benefit
80 70 60 I.-
w
50
2 W
0 2
40 30
e
20 10 0 TW
CS
WC
Fig 4 .-Improvements at 30 days and 6 months for the treadmill walk (TW), chair stand (CS), and weight carry (WC) tests .
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the practitioner by allowing the clinician to justify to managed care the benefits of surgical intervention . As managed care attempts to assume additional control over the benefits provided to the spine surgeon and to the patient, physicians should embrace the PBSI as a tool to validate their work and quantify their surgical outcomes . Similarly, the results of this study provide a cogent argument for the PBSI serving as a standard to objectively assess and document outcomes associated with new technology . The PBSI can serve as a link between a triad composed of physician, patient, and innovations in medical technology. Additionally, the index serves to validate the responsible use of technology in patient care . The allocation of financial resources must be based on objective data that support the partnership between the physician and new technology and eliminate the bias inherent in subjective reporting tools . As such, the impact of the PBSI is felt on the broad spectrum of health care delivery . In summary, the PBSI was developed as an alternative to many of the subjective instruments that are costly and cumbersome to implement . The PBSI offers the clinician an objective outcome measurement tool that is cost-effective and easily reproducible .
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