# Summary of Safety and Effectiveness Data {#summary-of-safety-and-effectiveness-data .unnumbered}

## I. General Information  {#i.-general-information .unnumbered}

**Device Generic Name:** Orthopedic Extracorporeal shock wave system

**Device Trade Name:** HealthTronics OssaTron^®\
^

**Applicant Name:** HealthTronics Surgical Services, Inc.

1841 W. Oak Parkway, Suite A

Marietta, Georgia 30062

**Date of Panel Recommendation:** None

Premarket Approval (PMA) Number: P990086/S3\
\
Date of Notice of Approval to Applicant: March 14, 2003\
\
This device was originally approved on October 12, 2000, for the limited
indication for use for performing extracorporeal shock wave (ESW)
treatment in patients with chronic proximal plantar fasciitis that has
failed to respond to conservative treatment. Chronic proximal plantar
fasciitis is defined as heel pain in the area of the insertion of the
plantar fascia on the medial calcaneal tuberosity that has persisted for
six months or more. The sponsor submitted this supplement to expand the
clinical indications. The updated clinical data to support the expanded
clinical indication for use for performing extracorporeal shock wave
(ESW) treatment in patients with chronic lateral epicondylitis (tennis
elbow) that has failed to respond to conservative treatment. The
preclinical test data were presented in the original PMA application.
For more information on the data which supported the original
indication, the summary of safety and effectiveness data for the
original PMA should be referenced. Written requests for copies of the
summary of safety and effectiveness data can be obtained from the
Dockets Management Branch (HFA-305), Food and Drug Administration, 5630
Fishers Lane, Room 1061, Rockville, MD, 20852 under Docket \# 01M-0271.

II\. Indications for Use

The OssaTron is indicated for use for performing extracorporeal shock
wave (ESW) treatment in patients with chronic lateral epicondylitis
(tennis elbow) that has failed to respond to conservative treatment.

Chronic Lateral Epicondylitis is defined as lateral epicondylitis that
has persisted for 6 months or more with a history of unsuccessful
conservative treatment.

III\. Contraindications

None known.

## IV. Warnings and Precautions {#iv.-warnings-and-precautions .unnumbered}

Please refer to the device labeling for a list of warnings and
precautions.

## V. Device Description {#v.-device-description .unnumbered}

## Principles of Operation:  {#principles-of-operation .unnumbered}

The HealthTronics OssaTron ESW system utilizes electrohydraulic \"spark
gap\" technology to generate shock waves: that is, a spark plug with two
opposing electrodes is positioned under water such that an electrical
discharge is directed to the first focal point (F~1~) of an ellipsoid
reflector. The electrodes are connected to a capacitor, which is charged
to the maximal voltage and then abruptly discharged. The underwater
discharge causes the explosive formation of a plasma channel and
evaporation of the water surrounding the electrodes. The spherical shock
wave that is released expands in the surrounding water and is reflected
by the walls of the ellipsoid reflector. Because of the geometric
properties of an ellipsoid reflector, all shock waves generated at F~1~
are reflected at its second focus (F~2~). Therefore, during an ESW
procedure, the device shock head and the patient are carefully aligned
and positioned such that target area to be treated is located at F~2~.

The OssaTron system incorporates all device components into a single
transportable unit. The major components include the Therapy Head, the
Control Cabinet, and the Control Console. A single-use electrode is
placed in the Therapy Head for each treatment.

**Therapy Head:** The Therapy Head integrates the brass ellipsoid, the
coupling membrane, the ELC 114 single-use electrode, the locating bow,
and the dummy electrode. The brass ellipsoid houses the electrode, and
reflects and focuses the shock waves. The therapy head is coupled to the
patient via the water filled coupling membrane covering the ellipsoid.
The ELC 114 electrode fits into the Therapy Head and extends into the
brass ellipsoid. The electrode receives a high energy current from the
Shock Wave Generator across the electrode tips, which produces the shock
wave. A dummy electrode that is incapable of firing is provided for use
only when transporting the device or when the device is stored. It is
installed in the ellipsoid in the same fashion as an active electrode.

The Therapy Head includes an anti-collision device that halts shock wave
generation and any mechanical movement of the device in the event of
therapy head collision with the patient or table. A Locating Bow affixed
to the Therapy Head allows for approximating the location of the shock
wave therapy focus and aligning it with the desired target site during
treatment. The Locating Bow can be rotated in 2 planes via the Control
Console. The therapy head unit is connected to the Control Cabinet via
an arm with 350-degree rotation capability. The water supply and voltage
cables attach to and rotate with the therapy arm.

**Control Console:** The Control Console includes a touch pad user
interface with LED display and a hand held shock wave release button.
The Control Console houses the two position key switch for turning power
supply to the device on and off. Touch keys are provided for setting the
desired shock wave energy (i.e., capacitor charge voltage in kV), and
the frequency of shock wave delivery (Hz). The Control Console display
shows these settings along with the total number of shocks delivered per
procedure. Movement of the Therapy Head and the locating bow are also
driven from the Control Console.

**Control Cabinet:** The Control Cabinet is the main body of the device.
It connects to standard hospital main 120 VAC single phase electrical
power supply. The Control Cabinet is mounted on a locking wheelbase and
incorporates 6 subcomponents: the charging unit, the shock wave
generator, the electric module, the water supply unit, the water valve
unit, and the motor drive units.

The charging unit delivers the high voltage to the shock wave generator,
which in turn triggers transformers that discharge high-voltage energy
across the electrode tips. The electric module is where power
connections are made; it supports and controls most of the high and low
power supplies to the system components. The water supply unit contains
a water tank, a safety thermostat for temperature control, a
desalination unit to set conductivity, and a small circulation pump and
provides conditioning, de-gassing and de-ionizing capabilities. The
water valve unit allows pressure control for setting the coupling
pressure during treatment, and for emptying and filling the therapy head
following electrode change. The Motor drive units enable rotation of the
Therapy Arm and Locating Bow, and movement of the Control Cabinet on the
wheelbase.

## VI. Adverse Effects of the Device on Health  {#vi.-adverse-effects-of-the-device-on-health .unnumbered}

A total 98 complications or adverse events were reported for the 225
treated subjects participating in this study. These 225 subjects
received 273 active ESW treatments and 90 placebo treatments. No
unanticipated adverse events or serious adverse events have occurred to
date in any subject participating in this investigation.

The most commonly reported procedure or device related complications
occurred during or shortly after the study procedure and included
localized swelling, bruising or petechiae at the treatment site (n=19)
and reactions to anesthetic agents (n=9). It is noted that all of the
reactions to anesthetic agents occurred at a single site, and may have
been related to the method of administering a regional block.

**Table 1: All Complications or Adverse Events, All Study Procedures**

+----------------+----------------+--------------+----------+---------+
|                | Active         | N            | Placebo  |         |
|                | Treatment      | onrandomized | T        |         |
|                | Group (n= 93)  | Group        | reatment |         |
|                |                |              | Group    |         |
|                |                | (n= 42)      |          |         |
|                |                |              | (n= 90)  |         |
+----------------+----------------+--------------+----------+---------+
| Event          | Total ESW      | Total ESW    | ESW      | Placebo |
|                |                |              | Pr       | Pro     |
|                | Procedures     | Procedures   | ocedures | cedures |
|                |                |              |          |         |
|                | (n= 131)¹      | (n= 56)²     | (n= 86)³ | (n= 90) |
+----------------+----------------+--------------+----------+---------+
| **Procedure    | 3 (2%)         | 1 (2%)       | 2 (2%)   | 3 (3%)  |
| related**      |                |              |          |         |
|                | 8 (6%)         | 7 (13%)      | 1 (1%)   | 3 (3%)  |
| Anesthesia     |                |              |          |         |
|                | 2 (2%)         | 0 (0%)       | 1 (1%)   | 0 (0%)  |
| Local          |                |              |          |         |
|                | 5 (4%)         | 0 (0%)       | 1 (1%)   | 0 (0%)  |
| Neuro          |                |              |          |         |
|                | **18 (14%)**   | **8 (14%)**  | **5      | **6     |
| Pain           |                |              | (6%)**   | (7%)**  |
|                |                |              |          |         |
| **Subtotal**   |                |              |          |         |
+----------------+----------------+--------------+----------+---------+
| **Not          | 28 (21%)       | 4 (7%)       | 15 (17%) | 14      |
| Procedure      |                |              |          | (16%)   |
| related**      | 0 (0%)         | 0 (0%)       | 0 (0%)   |         |
|                |                |              |          | 0 (0%)  |
| Other          | **28 (21%)**   | **4 (7%)**   | **15     |         |
|                |                |              | (17%)**  | **14    |
| Tear           |                |              |          | (16%)** |
|                |                |              |          |         |
| **Subtotal**   |                |              |          |         |
+----------------+----------------+--------------+----------+---------+
| **TOTAL**      | **46 (35%)**   | **12 (21%)** | **20     | **20    |
|                |                |              | (23%)**  | (22%)** |
+----------------+----------------+--------------+----------+---------+
| Total events:  | **78/273       |              |          | **20/90 |
|                | (29%)**        |              |          | (22%)** |
| Active         |                |              |          |         |
| treatment      |                |              |          |         |
|                |                |              |          |         |
| Placebo        |                |              |          |         |
| treatment      |                |              |          |         |
+----------------+----------------+--------------+----------+---------+
| ¹Total ESW     |                |              |          |         |
| procedures     |                |              |          |         |
| include 93     |                |              |          |         |
| primary        |                |              |          |         |
| procedures and |                |              |          |         |
| 38 repeat      |                |              |          |         |
| treatments in  |                |              |          |         |
| 38 subjects    |                |              |          |         |
| who failed to  |                |              |          |         |
| meet success   |                |              |          |         |
| criteria at 8  |                |              |          |         |
| weeks          |                |              |          |         |
|                |                |              |          |         |
| ²Total ESW     |                |              |          |         |
| procedures     |                |              |          |         |
| include 42     |                |              |          |         |
| primary        |                |              |          |         |
| procedures and |                |              |          |         |
| 14 repeat      |                |              |          |         |
| treatments in  |                |              |          |         |
| 13 subjects    |                |              |          |         |
| who failed to  |                |              |          |         |
| meet success   |                |              |          |         |
| criteria at 8  |                |              |          |         |
| weeks          |                |              |          |         |
|                |                |              |          |         |
| ³A total of 86 |                |              |          |         |
| placebo        |                |              |          |         |
| treatment      |                |              |          |         |
| patients       |                |              |          |         |
| underwent      |                |              |          |         |
| primary ESW    |                |              |          |         |
| treatment      |                |              |          |         |
| after failing  |                |              |          |         |
| to meet        |                |              |          |         |
| success        |                |              |          |         |
| criteria at 8  |                |              |          |         |
| weeks post     |                |              |          |         |
| placebo        |                |              |          |         |
| treatment      |                |              |          |         |
+----------------+----------------+--------------+----------+---------+

**Potential Adverse Effects**

The potential adverse effects of ESW treatment with the OssaTron
include:

-   Pain during the ESW treatment;

-   Localized numbness, tingling or decreased sensation in the foot or
    at the site of shock wave delivery;

-   Local subcutaneous hematoma, bruising, or petechial bleeding in the
    foot/elbow or at the treatment site;

-   Misdirection of ESW energy to a major nerve or blood vessel,
    resulting in injury;

-   Anesthesia complications, including allergic reactions to local or
    regional anesthetic agents; and

-   Rupture of plantar fascia.

## VII. Alternate Practices or Procedures  Alternative therapies include: {#vii.-alternate-practices-or-procedures-alternative-therapies-include .unnumbered}

-   Rest

-   Application of cold to the symptomatic region

-   Non-steroidal anti-inflammatory medications

-   Physical therapy

-   Surgical treatments

## VIII. Marketing History  {#viii.-marketing-history .unnumbered}

The OssaTron has been marketed in the European Union, Switzerland, Iran,
Saudi Arabia, Thailand, People\'s Republic of China, Australia and
Taiwan. HealthTronics Surgical Services Inc. has placed approximately 56
OssaTron systems throughout the United States since PMA approval on
October 12, 2000. The OssaTron system has never been withdrawn from
marketing for any reason related to safety or effectiveness of the
device.

## IX. Summary of Preclinical Testing  {#ix.-summary-of-preclinical-testing .unnumbered}

A summary of the preclinical testing of the OssaTron may be found in
SSED for the original PMA application.

## X. Summary of Clinical Studies  {#x.-summary-of-clinical-studies .unnumbered}

### A. Study Design  {#a.-study-design .unnumbered}

The clinical study of the OssaTron was a multicenter, randomized, sham
controlled clinical trial to determine the safety and effectiveness of
ESW treatment for chronic lateral epicondylitis. The study protocol was
approved for a total enrollment of 250 subjects, including 100 subjects
randomized to either active ESW treatment or sham treatment with the
OssaTron and 50 nonrandomized subjects to allow each investigator to
complete training requirements for performing the OssaTron procedure.
The patients were followed up at 4 weeks and 8 weeks after the
treatment, at the 8 weeks post treatment follow up a success / fail
assignment was made based on three criteria: Investigator assessment of
pain, subject self-assessment of pain and the use of pain medications.

A minimum of two investigators participated in the study at each site so
that one investigator could serve as the blinded evaluator for baseline
and post treatment follow up visits. The non-blinded investigator
performed the study procedures as follows: Each study subject received a
local anesthetic or a bier block prior to the study procedure. The
affected arm was then draped from the view of the study subject. Each
subject assigned to active treatment then underwent an ESW procedure
with a total of 1500 shocks delivered at a power setting of 18kV. The
average active treatment time was 20.5 minutes. For subjects assigned to
sham treatment, a Styrofoam block was placed against the coupling
membrane of the shock head to absorb the shock waves. A fluid-filled IV
bag was then placed between the Styrofoam block and the subject's elbow
to mimic the feel of the coupling membrane, and 1500 shocks were then
delivered at 18kV.

### B. Inclusion and Exclusion Criteria  {#b.-inclusion-and-exclusion-criteria .unnumbered}

Enrollment was limited to patients with the following criteria:

-   History of chronic lateral epicondylitis persisting for at least 6
    months;

-   Failure to respond to at least 3 attempts at conservative treatment:
    one prior courses of non-invasive treatment, including physical
    therapy (e.g., stretching exercises) and the use of an orthotic
    device; and two prior course of pharmacological treatment such as
    NSAID's or cortisone injections;

-   Investigator assessment of pain at the point of tenderness over the
    affected lateral epicondyle [\>]{.underline}5.0 on a 10 cm. Visual
    Analog Scale (VAS) and subject self-assessment of pain during
    activity [\>]{.underline}5.0 cm on a 10 cm VAS;

-   Female subjects must not be pregnant;

-   Other causes for elbow pain have been ruled out, such as vascular
    insufficiency or neuropathy of the upper extremities;

-   Concomitant pathology has been ruled out, including severe
    osteoarthritis; rheumatoid arthritis, osteoporosis; metabolic
    disorders, malignancies; Paget's disease; an acute, subacute or
    chronic osteomyelitis or systemic infection; or fracture of the
    affected arm; and

-   21 years of age or older to assure all subjects would be skeletally
    mature.

+------------------------+--------------------+------------------------+
| **Table 2**            |                    |                        |
|                        |                    |                        |
| **Demographics of      |                    |                        |
| Patients Enrolled in   |                    |                        |
| Lateral Epicondylitis  |                    |                        |
| Study**                |                    |                        |
+------------------------+--------------------+------------------------+
| Characteristics        | Active Treatment   | Placebo Treatment      |
|                        | Patients           | Patients               |
|                        |                    |                        |
|                        | (N=93)             | (N=90)                 |
+------------------------+--------------------+------------------------+
| Age (years)            | 44                 | 46                     |
|                        |                    |                        |
| Mean:                  | 22-66              | 32-71                  |
|                        |                    |                        |
| Range:                 |                    |                        |
+------------------------+--------------------+------------------------+
| Gender                 | 46                 | 41                     |
|                        |                    |                        |
| Male:                  | 47                 | 49                     |
|                        |                    |                        |
| Female:                |                    |                        |
+------------------------+--------------------+------------------------+
| Affected Arm           | 64                 | 69                     |
|                        |                    |                        |
| Right:                 | 29                 | 21                     |
|                        |                    |                        |
| Left:                  |                    |                        |
+------------------------+--------------------+------------------------+
| Prior Therapies        | 26                 | 25                     |
|                        |                    |                        |
| Cortisone Injections:  | 15                 | 12                     |
|                        |                    |                        |
| NSAID's:               | 52                 | 53                     |
|                        |                    |                        |
| Both:                  | 93                 | 90                     |
|                        |                    |                        |
| Physical Therapy:      |                    |                        |
+------------------------+--------------------+------------------------+
| Symptom Duration       | 684.37             | 783.79                 |
| (Days)                 |                    |                        |
|                        | 161-4920           | 126-8089               |
| Mean:                  |                    |                        |
|                        |                    |                        |
| Range:                 |                    |                        |
+------------------------+--------------------+------------------------+

**\
C. Evaluation Methods**

#### Investigator Assessment:

The investigator blinded to randomization assignment assessed the
subject's elbow pain by applying pressure on the affected lateral
epicondyle. The investigators used a pressure sensor to record the
amount of pressure applied to elicit the baseline response, and
thereafter to apply the same amount of pressure at each follow up
assessment to assure consistency in this evaluation. To be eligible for
study participation, a subject must have reported a pain score of 5.0 or
greater on a 10 cm VAS during the investigator's initial assessment.

#### Subject Self-Assessment of Pain:

Each subject was asked to provide a self-assessment of the amount of
pain experienced in the affected elbow during activity, reported
according to a 10 cm VAS. To meet study inclusion criteria, the
subject's initial VAS must have been moderate to severe, i.e., 5.0 cm or
greater on a 10 cm VAS.

#### D. Primary Effectiveness Measurements {#d.-primary-effectiveness-measurements .unnumbered}

The investigator who was blinded to randomization assignment determined
the initial "success/fail" status for each study subject, who must meet
all 3 of the following criteria in order for an overall status of
"success" to be assigned at the 8 week follow-up visit.

-   Investigator's assessment of elbow pain: A minimum 50% improvement
    over baseline, and a score no greater than 4.0 on VAS.

-   Subject's self-assessment of pain with activity: A minimum 50%
    improvement over baseline with a score no greater than 4.0 on VAS.

-   Use of pain medications: None or rare pain medication use at the 8
    week visit. Rare medication use was defined as no more than three
    does of medication during the week immediately prior to being
    evaluated.

#### E. Data Analysis and Results {#e.-data-analysis-and-results .unnumbered}

**1. Study Enrollment**

A total of 225 subjects were enrolled and treated, of these 42 subjects
were nonrandomized subjects enrolled to accomplish investigator training
requirements, leaving 183 randomized subjects.

Twenty-one of the 225 subjects (9.0%) withdrew from the study or were
lost to follow up prior to the 8 week follow up visit. Three of the 21
subjects lost to follow-up were nonrandomized subjects, and the
remaining 18 were randomized subjects. A total of 165 randomized and 39
nonrandomized subjects were assigned a "success/fail" status based on 8
week follow up findings.

The Table 3 summarizes the 8 week follow up status for all study
subjects.

Table 3: Study Participation Status-Follow Up at 8 Weeks

+------------+-------------+-------------+--------------+-------------+
|            | **Active    | **Placebo   | **N          | **TOTAL**   |
|            | Treatment   | Treatment   | onrandomized |             |
|            | Subjects**  | Subjects**  | Subjects**   |             |
+------------+-------------+-------------+--------------+-------------+
| Total      | 93          | 90          | 42           | 225         |
| Subjects   |             |             |              |             |
| Treated    |             |             |              |             |
+------------+-------------+-------------+--------------+-------------+
| Subjects   | 0           | 0           | 0            | 0           |
| less than  |             |             |              |             |
|            |             |             |              |             |
| 8 Weeks    |             |             |              |             |
| since      |             |             |              |             |
| Treatment  |             |             |              |             |
+------------+-------------+-------------+--------------+-------------+
| Total      | 93          | 90          | 42           | 225         |
| Subjects   |             |             |              |             |
| Eligible   |             |             |              |             |
| for 8 Week |             |             |              |             |
| Follow Up  |             |             |              |             |
+------------+-------------+-------------+--------------+-------------+
| Total Lost | 11          | 7           | 3            | 21          |
| to Follow  |             |             |              |             |
| Up or      |             |             |              |             |
| Withdrawn  |             |             |              |             |
+------------+-------------+-------------+--------------+-------------+
| Total      | 82          | 83          | 39           | 204         |
| Subjects   |             |             |              |             |
| with 8     |             |             |              |             |
| Week       |             |             |              |             |
| Status     |             |             |              |             |
+------------+-------------+-------------+--------------+-------------+

**2. Gender Analysis:**

The study population was evenly divided between male and female.
Subjects' ages at the time of study enrollment ranged from 22 years to
72 years, mean 45.7 years. Subjects were predominantly Caucasian.

**3. Duration of Symptoms at Baseline:**

The study protocol required that each subject must have had symptoms of
chronic lateral epicondylitis for at least six months prior to study
enrollment. The table above shows the mean duration of symptoms for
subjects randomized to active treatment was 684 days (1.9 years), range
5 months to 13 years. For subjects randomized to placebo treatment, the
mean duration of symptoms was 783.79 days (2.1 years), range 4 months to
22 years.

**4. Effectiveness Analysis**

**a. Investigator Assessment:**

The subjects randomized to active ESW treatment improved from a mean
baseline VAS score of 7.73 to 3.64 at 8 weeks as shown in the table
below. The median 8 week VAS score was 3.35. Forty-three of the 82
subjects (52.4%) met the success criteria for this parameter. The
subjects randomized to placebo treatment improved from a mean baseline
VAS score of 7.81 to 5.17 at 8 weeks. The median 8 week VAS score was
5.5. Twenty-six of the 83 subjects (31.3%) met the success criteria
(minimum 50% improvement and VAS score of 4.0 or less) for this
parameter. The difference between the active treatment and placebo group
was statistically significant.

Table 4: Investigator Assessment -- Baseline through 8 Weeks

+-------------------+-----------+------------+------------+------------+
|                   |           | **         | **4        | **8        |
|                   |           | Baseline** | Weeks**    | Weeks**    |
+-------------------+-----------+------------+------------+------------+
| Active ESW        | *N*       | 93         | 84         | 82         |
| Treatment         |           |            |            |            |
|                   | Mean      | 7.73(1.38) | 5.02(2.73) | 3.64(2.52) |
|                   | (StD)     |            |            |            |
|                   |           | 7.6        | 5.3        | 3.35       |
|                   | Median    |            |            |            |
|                   |           | 4.7-10     | 0-10       | 0-9.7      |
|                   | Range     |            |            |            |
+-------------------+-----------+------------+------------+------------+
| Placebo Treatment | *N*       | 90         | 80         | 83         |
|                   |           |            |            |            |
|                   | Mean      | 7.81(1.50) | 5.48(3.31) | 5.17(3.13) |
|                   | (StD)     |            |            |            |
|                   |           | 7.7        | 6.05       | 5.5        |
|                   | Median    |            |            |            |
|                   |           | 4.9-10     | 0-10       | 0-10       |
|                   | Range     |            |            |            |
+-------------------+-----------+------------+------------+------------+

**b. Subject Self-Assessment of Pain:**

At each study visit subjects were asked to report the amount of pain
experienced over the past week during activity. The subject recorded the
response on the 10 cm VAS scale. The subjects randomized to active ESW
treatment improved from a mean VAS baseline score of 7.37 to 3.53 at 8
weeks. The median 8 week VAS score was 2.9. Forty-eight of the 82
subjects (58.6%) met the success criteria (minimum 50% improvement and
VAS score of 4.0 or less) for this parameter.

The subjects randomized to placebo treatment improved from a mean
baseline VAS score of 7.76 to 4.37 at 8 weeks. The median 8 week VAS
score was 4.2. Thirty-six of the 83 subjects (43.4%) met the success
criteria (minimum 50% improvement and VAS score of 4.0 or less) for this
parameter. The difference between the active treatment and placebo group
was not statistically significant.

Table 5: Subject Self-Assessment -- Baseline through 8 Weeks

+-------------------+-----------+------------+------------+------------+
|                   |           | **         | **4        | **8        |
|                   |           | Baseline** | Weeks**    | Weeks**    |
+-------------------+-----------+------------+------------+------------+
| Active ESW        | *N*       | 93         | 84         | 82         |
| Treatment         |           |            |            |            |
|                   | Mean      | 7.37(1.21) | 4.53(2.26) | 3.53(2.53) |
|                   | (StD)     |            |            |            |
|                   |           | 7.4        | 4.75       | 2.9        |
|                   | Median    |            |            |            |
|                   |           | 4.6-10     | 0-9        | 0-8.4      |
|                   | Range     |            |            |            |
+-------------------+-----------+------------+------------+------------+
| Placebo Treatment | *N*       | 90         | 80         | 83         |
|                   |           |            |            |            |
|                   | Mean      | 7.76(1.31) | 4.92(2.49) | 4.37(2.58) |
|                   | (StD)     |            |            |            |
|                   |           | 7.95       | 4.6        | 4.2        |
|                   | Median    |            |            |            |
|                   |           | 4.9-10     | 0-9.9      | .02-9.7    |
|                   | Range     |            |            |            |
+-------------------+-----------+------------+------------+------------+

**c. Use of Pain Medications:**

Each subject was asked to report the medications he or she was taking
for pain at the initial study evaluation visit, and thereafter to keep
track of all medications taken for pain throughout the course of study
participation. The use of pain medications was then classified according
to the frequency of use: chronic, frequent, occasional, rare or none.
Exact definitions for these classifications were provided in the study
protocol. In order to be assigned a status "success" for this parameter,
the study protocol required that the subject could be taking none or
rare pain medications at the time of the 8 week follow up visit. The
results are shown in the following table.

At baseline, 56/93 (60.2%) active treatment subjects were routinely
taking medication for elbow pain. This had been reduced to 24/82 (29.1%)
by the 8 week visit. Seventy-one of 82 subjects followed to 8 weeks
(86.6%) met the success criteria for this parameter. At baseline, 56/90
(62.2%) placebo treatment subjects were routinely taking medication for
elbow pain. This had been reduced to 26/83 (31.3%) by the 8 week visit.
Sixty-one of 83 subjects followed to 8 weeks (73.5%) met the success
criteria for this parameter. The difference between the active treatment
and placebo group was not statistically significant.

Table 6: Medication Requirements -- Baseline through 8 Weeks

+-------------------+-----------+------------+------------+------------+
|                   | **B       | **         | **4        | **8        |
|                   | aseline** | Medication | Weeks**    | Weeks**    |
|                   |           | Requ       |            |            |
|                   |           | irements** |            |            |
+-------------------+-----------+------------+------------+------------+
| Active ESW        | None: 37  | None       | 49         | 58         |
| Treatment         |           |            |            |            |
|                   | NSAID's:  | Rare       | 14         | 13         |
|                   | 46        |            |            |            |
|                   |           | Occasional | 8          | 2          |
|                   | Other: 10 |            |            |            |
|                   |           | Frequent   | 5          | 2          |
|                   |           |            |            |            |
|                   |           | Chronic    | 8          | 7          |
+-------------------+-----------+------------+------------+------------+
| Placebo Treatment | None: 34  | None       | 48         | 57         |
|                   |           |            |            |            |
|                   | NSAID's:  | Rare       | 8          | 4          |
|                   | 52        |            |            |            |
|                   |           | Occasional | 9          | 9          |
|                   | Other: 4  |            |            |            |
|                   |           | Frequent   | 10         | 8          |
|                   |           |            |            |            |
|                   |           | Chronic    | 5          | 5          |
+-------------------+-----------+------------+------------+------------+

**d. Overall Success/Fail Status:**

As shown in Table 7, the results show a statistically significant
difference between the OssaTron and placebo groups for the composite
endpoint at 8 weeks. Of the 82 subjects followed to 8 weeks after an
active OssaTron ESW treatment, 33 (40%) met all 3 success criteria,
compared to 20 of 83 placebo treated subjects (24 %) who met all 3
criteria, a difference that is significant at a *p* level of 0.043.

The majority of the treatment effect was observed in the blinded
evaluator's assessment of elbow pain. The subjects' self-assessments of
pain with activity did not indicate large treatment differences through
8 weeks, and were not statistically different. The active treatment
subjects showed greater improvement use of pain medications and in SF-36
scores than did placebo subjects. However, none of the primary or
secondary outcome measurements demonstrated statistically significant
treatment differences.

> Table 7:
>
> 8 Week Response to Treatment-All Components of Success, All Subjects
> Randomized

+-----------------+-----------------+-----------------+-----------------+
| **Measure**     | **Active ESW    | **Placebo       | **p Value**     |
|                 | Treatment**     | Treatment**     |                 |
|                 |                 |                 |                 |
|                 | **(n=93)**      | **(n=90)**      |                 |
+-----------------+-----------------+-----------------+-----------------+
| Investigator    | 45 (48%)        | 26 (29%)        | 0.007           |
| Assessment      |                 |                 |                 |
+-----------------+-----------------+-----------------+-----------------+
| Self            | 51 (55%)        | 37 (41%)        | 0.063           |
| Assessment,     |                 |                 |                 |
| Pain during     |                 |                 |                 |
| activity        |                 |                 |                 |
+-----------------+-----------------+-----------------+-----------------+
| Medication Use  | 75 (81%)        | 63 (70%)        | 0.095           |
+-----------------+-----------------+-----------------+-----------------+
| Composite: All  | 33 (35%)        | 20 (22%)        | 0.043           |
| 3 Components    |                 |                 |                 |
+-----------------+-----------------+-----------------+-----------------+

**\
5. Primary Safety Measurements**

As shown in Table 1, a total of 98 complications or adverse events were
reported for the 225 treated subjects participating in this study. These
225 subjects received 273 active ESW treatments and 90 placebo
treatments. No unanticipated adverse events or serious adverse events
have occurred to date in any subject participating in this
investigation.

The most commonly reported procedure or device related complications
occurred during or shortly after the study procedure and included
localized swelling, bruising or petechiae at the treatment site (n=19)
and reactions to anesthetic agents (n=9). It is noted that all of the
reactions to anesthetic agents occurred at a single site, and may have
been related to the method of administering a regional block.

## XI. Panel Recommendation  {#xi.-panel-recommendation .unnumbered}

In accordance with the provisions of Section 515(c)(2) of the Act as
amended by the Safe Medical Devices Act of 1990, this PMA supplement was
not referred to the Orthopedics Devices Panel or the General Surgery
Devices Panel, FDA advisory committees, because the information in the
PMA substantially duplicated information previously reviewed by this
panel.

## XII. FDA Decision  {#xii.-fda-decision .unnumbered}

The clinical study results provide reasonable assurance that use of the
HealthTronics OssaTron for the treatment of patients with chronic
lateral epicondylitis is a safe and effective alternative for patients
who have a history of unsuccessful conservative treatment.

In addition, the applicant's manufacturing facility was inspected and
found to be in compliance with the Quality Systems Regulation (21 CFR
820).

CDRH issued an approval order on March 14, 2003.

## XIII. Approval Specifications {#xiii.-approval-specifications .unnumbered}

Directions for use: See labeling

Hazard to Health from Use of the Device: see Warnings, Precautions, and
Adverse Events sections in the labeling.

Conditions of Approval: See approval order