Keywords elbow - tendons - ultrasonography - physical examination - tennis elbow
Introduction
Lateral elbow epicondylitis (LEE) is an orthopedic condition affecting the tendon of the extensor digitorum communis muscle. It is a very frequent condition, presenting with tendon degeneration and pain in the lateral region of the elbow.[1 ] The incidence of LEE is roughly 4/1,000 people per year, affecting a wide variety of workers and athletes who perform repetitive elbow and wrist movements. Its peak incidence is from the 4th to the 6th decades of life.[2 ]
Despite being called “tennis elbow”, LEE affects a large number of workers, ranging from office to industrial production line workers. In a study conducted in Washington, USA, between 1987 and 1995, LEE accounted for 11.7% of work-related injury complaints.[3 ]
The pathophysiology of LEE is not fully understood. Histopathological changes observed in the tendon include increased fibroblast concentration, vascular hyperplasia, and collagen fiber disorganization; as such, the condition can be defined as an elbow tendinopathy.[2 ]
Ultrasound (US) is the diagnostic method of choice to confirm LEE diagnosis, associated with physical examination and clinical history findings.[3 ]
The treatment of LEE remains challenging, with a high rate of poor outcomes.[2 ] Despite being a relatively common condition, there is little scientific evidence to support an algorithm for LEE treatment.[4 ]
[5 ]
[6 ]
The evaluation of LEE treatment outcomes is also challenging. There are several scales for elbow function analysis, such as: the Mayo elbow performance score (MEPS), disabilities of the arm, shoulder and hand (DASH) and upper extremity function scale (UEFS). These scales not only evaluate LEE-associated painful symptoms and associated functional loss, but also various trauma-related factors, such as stiffness and instability. As such, score values are increased, generating a false impression of discrete elbow involvement in LEE because the limiting factor for elbow functionality in this condition is pain with preserved range of motion and joint stability.[7 ]
[8 ]
[9 ]
[10 ]
The Patient-rated Tennis Elbow Evaluation (PRTEE) scale was developed by MacDemid[7 ] and other authors[8 ]
[9 ], in 1999, specifically to evaluate LEE cases. In 2005, it was modified to its current model by the same group of researchers. The PRTEE consists of 15 items, which are subdivided into 2 parts; the 1st part contains 5 items assessing pain, ranging from 0 to 10 according to pain intensity, whereas the second part has 10 items assessing elbow function in daily activities, in which 0 indicates total capacity and 10 refers to total incapacity. Results from the second part are divided by two and added to the results from the first part; the total score ranges from 0, indicating no involvement, to 100 points, referring to the maximum degree of limb involvement by LEE[10 ]
[11 ]([Figure 1 ]).
Fig. 1 Patient-Rated Tennis Elbow Evaluation (PRTEE) scale.
Subjective elbow value (SEV) is a single numerical value obtained by asking the patient the percentage of impaired functional activity in the affected elbow that can range from 0 to 100; in which 100 corresponds to an elbow with normal function and 0 to an elbow with total inability to perform daily routine and professional activities.[11 ]
The present study intended to verify if the SEV scale presented similar results to those of the PRTEE scale for the evaluation of patients with untreated LEE.
Materials and Methods
This study was conducted from July 2016 to March 2017. In total, 53 patients were evaluated at the shoulder and elbow outpatient facility with a diagnostic hypothesis of LEE; 37 subjects met the inclusion and exclusion criteria for this study ([Table 1 ]).
Table 1
PATIENTS
AGE
GENDER
OCCUPATION
AFFECTED SIDE
ROM
COZEN/MILLS/ GARDNER
PRTEE
SEV
(F/E; P/S)*
01
52
Female
HOUSEMAID
RIGHT
0-140; 75-80
POS/POS/POS
80
30%
02
56
Male
RETIRED
LEFT
0-140; 75-80
POS/POS/POS
77
20%
03
66
Male
COMMERCIAL REPRESENTATIVE
RIGHT
0-140; 90-90
POS/POS/NEG
60
30%
04
48
Female
HOUSEMAID
RIGHT
5-140; 75-85
POS/POS/NEG
63
50%
05
53
Female
TEACHER
RIGHT
0-130; 70-80
POS/POS/POS
74
40%
06
50
Female
HAIRDRESSER
RIGHT
0-120; 65-80
POS/POS/NEG
87
30%
07
46
Female
CLEANING ATTENDANT
RIGHT
0-140; 75-80
POS/POS/NEG
93
50%
08
49
Female
CLEANING ATTENDANT
RIGHT
0-120; 70-80
POS/POS/POS
75
45%
09
51
Female
UNEMPLOYED
RIGHT
0-130; 65-75
POS/POS/POS
76
30%
10
44
Female
HOUSEMAID
RIGHT
0-120; 60-80
POS/POS/NEG
77
60%
11
48
Female
RADIOLOGY TECHNICIAN
RIGHT
0-140; 70-85
POS/NEG/NEG
68
70%
12
57
Male
TEACHER
RIGHT
0-120; 75-80
POS/POS/NEG
69
50%
13
45
Female
MANICURIST
RIGHT
0-130; 70-85
POS/POS/NEG
74
30%
14
49
Female
FINANCIAL EXECUTIVE
RIGHT
0-140; 75-85
POS/POS/POS
85
90%
15
59
Male
TAXI DRIVER
RIGHT
0-140;90-90
NEG/POS/POS
73
60%
16
55
Male
LAWYER
RIGHT
0-140;90-90
POS/POS/POS
66
30%
17
60
Female
HOUSEKEEPER
RIGHT
0-140;90-90
POS/POS/POS
72
30%
18
40
Female
ELDERLY CAREGIVER
RIGHT
0-140;90-90
NEG/NEG/POS
71
25%
19
51
Male
HAIRDRESSER
LEFT
0-140;80-80
NEG/NEG/POS
74
50%
20
43
Male
DOORMAN
RIGHT
0-130;80-80
POS/POS/POS
73
70%
21
39
Female
SEAMSTRESS
RIGHT
0-140;90-90
POS/POS/POS
78
35%
22
44
Female
HOUSEMAID
RIGHT
0-140;90-90
POS/POS/POS
70
55%
23
45
Male
DRIVER
LEFT
0-140;90-90
POS/POS/POS
60
45%
24
46
Female
CLEANING ATTENDANT
LEFT
0-140; 80-90
POS/NEG/POS
75
40%
25
56
Male
TEACHER
RIGHT
0-130; 75-80
POS/POS/POS
68
30%
26
42
Female
RADIOLOGY TECHNICIAN
LEFT
0-140; 80-90
POS/POS/NEG
62
50%
27
54
Female
NURSE ASSISTANT
LEFT
0-140; 90-90
POS/NEG/NEG
60
50%
28
45
Male
RETIRED
RIGHT
0-140; 80-90
POS/POS/NEG
65
30%
29
33
Female
HAIRDRESSER
RIGHT
0-130;80-80
POS/POS/POS
81
70%
30
47
Female
HOUSEMAID
RIGHT
0-140;80-90
POS/POS/POS
63
60%
31
45
Female
COMMERCIAL REPRESENTATIVE
RIGHT
0-140;90-90
POS/POS/POS
76
80%
32
40
Female
HOUSEKEEPER
RIGHT
0-140;90-90
POS/POS/POS
70
60%
33
54
Female
HAIRDRESSER
RIGHT
0-140;90-90
NEG/POS/POS
82
80%
34
37
Female
HAIRDRESSER
RIGHT
0-140;90-90
NEG/NEG/POS
60
80%
35
47
Female
LAUNDRY WORKER
RIGHT
0-130;80-80
POS/POS/POS
66
60%
36
36
Male
BRICKLAYER ASSISTANT
LEFT
0-130;90-90
POS/POS/POS
67
70%
37
38
Male
MECHANIC
RIGHT
0-140;90-90
POS/NEG/NEG
68
60%
The inclusion criteria were: compatible findings at clinical history and physical examination, complemented by ultrasound findings, normal results at elbow radiographs, and lack of any previous treatment.
Clinical criteria used for diagnosis included chronic pain at the lateral aspect of the elbow, defined as pain for more than 12 weeks, pain during lateral epicondyle palpation and positivity in at least two of the following physical examination tests: pain during wrist or finger extension against resistance with the elbow at 90 degrees of flexion (Cozen test),[12 ] pain with the elbow in extension and passive wrist extension (Mills test),[12 ] pain during elevation from chair with pronated and semiflexed wrist (Gardner test),[12 ] pain at resistive supination,[12 ] and pain during passive stretch of the supinator muscle[12 ] ([Figure 2A-B ]). All photos belong to the authors' archives and pictures of all physical examination tests would exceed the maximum number of pictures allowed by this journal.
Fig. 2 (A ) Cozen test, (B ) Mills test.
The exclusion criteria were: previous history of rheumatologic disease and/or arthritis, orthopedic disorders affecting the elbow other than LEE, acute elbow pain, diabetes mellitus, pregnancy, neurological diseases, peripheral neuropathies, recent acute upper limb trauma, previous surgery on the affected limb, and chronic polyarthralgia.
The clinical diagnosis was made and then confirmed by an ultrasound examination; an x-ray of the affected elbow was also performed to exclude other orthopedic joint conditions.[11 ]
The research project was duly approved by the research ethics committee of the institution. All patients participating in this study signed an informed consent form.
The 37 patients diagnosed with lateral epicondylitis were evaluated using the PRTEE and SEV scales during an outpatient visit at our hospital.[8 ]
[9 ]
[10 ]
[11 ]
An Excel spreadsheet (Microsoft Corp., Redmond, WA, USA) was used for data organization. The IBM SPSS statistical package, version 23.0 (IBM Corp., Armonk, NY, USA) was used for results analysis. The Mann-Whitney test was used to verify possible differences between genders and to analyze the relationship between laterality and SEV.
The Spearman's correlation analysis was used to evaluate the degree of relationship between SEV and PRTEE. Values were considered statistically significant when p- value was greater than or equal to 5% (p ≥0.05).
Results
In total, 25 patients were female (67.6%); the mean patients' age was 47 years, 10 months-old, and 27 (79.4%) subjects performed activities associated with repetitive elbow or wrist movements. At the physical examination tests, 86.4%, 81%, and 67.5% of the patients presented positive results at the Cozen, Mills, and Gardner tests, respectively.
The Mann-Whitney test was used to evaluate whether gender and laterality represented important factors in SEV results and found no statistically significant differences. Therefore, the fact that the patient affected by LEE was male or female did not influence the degree of elbow involvement (p = 0.179); similarly, whether the affected side was the right or left one did not represent a statistically significant factor (p = 0.433) ([Table 2 ]).
Table 2
Variable
Gender
n
Average
Standard deviation
Minimum
Maximum
25th percentile
50th percentile (Median)
75th percentile
Significance (p )
SEV
Female
25
54.80%
18.62%
30.00%
100.00%
40.00%
50.00%
70.00%
0.179
Male
12
45.42%
17.25%
20.00%
70.00%
30.00%
47.50%
60.00%
Total
37
51.76%
18.49%
20.00%
100.00%
32.50%
50.00%
65.00%
Variable
Gender
n
Average
Standard deviation
Minimum
Maximum
25th percentile
50th percentile (Median)
75th percentile
Significance (p)
SEV
Right
30
53.00%
19.24%
30.00%
100.00%
30.00%
52.50%
70.00%
0.1433
Left
7
46.43%
14.92%
20.00%
70.00%
40.00%
50.00%
50.00%
Total
37
51.76%
18.49%
20.00%
100.00%
32.50%
50.00%
65.00%
The Spearman correlation analysis evaluated if there was a statistically significant relationship between the results obtained with the SEV and PRTEE scales; since this relationship actually existed, results were equivalent when both scales were applied (p = 0.017) ([Table 3 ]).
Table 3
Variable
Statistical Analysis
SEV
AGE
Coefficient of correlation (r)
-0.409
Calculated significance (p)
0.012
n
37
PRTEE
Coefficient of correlation (r)
+0.391
Calculated significance (p)
0.017
n
37
Discussion
Previous researches have shown that the PRTEE scale is a satisfactory method for evaluating LEE patients, since it was created specifically for the study of these subjects. The PRTEE scale presents a good correlation with clinical complaints in subjects with LEE-associated functional limitations.[7 ]
[13 ] In several case series, the PRTEE scale demonstrated a good sensitivity in the evaluation of LEE patients, but it is very extensive and difficult for the examiner to memorize; these are its main limitations for its use in clinical practice. The PRTEE had good sensitivity and specificity in the evaluation of both acute and chronic LEE cases.[7 ]
[13 ]
[14 ]
Consistent with the literature, our study also demonstrated that SEV is a simple and easy-to-use scale for the clinical investigation of the degree of functional impairment in patients with elbow conditions, being easily understood by the subject and rapidly memorized by the physician. In addition, SEV was developed to evaluate any elbow condition.[15 ]
A study conducted in 2014 observed that there was a moderate statistical relationship between SEV and MEPS in the evaluation of patients with elbow tendon conditions; this paper showed that, despite being simple, SEV is as good as a more complex scale, such as MEPS, in evaluating these diseases.[16 ]
In 2017, Ernstbrunner observed similar results in the postoperative evaluation of patients undergoing total elbow arthroplasty using MEPS or SEV scales.[17 ]
A 2011 study demonstrated similar results between SEV and MEPS in the evaluation of patients submitted to an anconeus graft at the elbow for chronic posterior skin defect with no joint involvement; this finding confirmed information from the previous study that SEV is a very appropriate scale for elbow conditions.[18 ]
Our study observed a statistically significant relationship between results obtained with the SEV and PRTEE scales in the evaluation of patients diagnosed with LEE.
Conclusion
Subjective elbow value is a functional scale with statistically similar results to those of PRTEE in the evaluation of untreated LEE patients.