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Basal Joint Osteoarthritis of the Thumb: Ligament Reconstruction and Tendon Interposition Versus Hematoma Distraction Arthroplasty
SCIENTIFIC ARTICLE
Basal Joint Osteoarthritis of the Thumb: Ligament Reconstruction and Tendon Interposition Versus Hematoma Distraction Arthroplasty Brinkley K. Sandvall, BS, Todd E. Cameron, DO, David T. Netscher, MD, Michael J. Epstein, MD, Kimberly Goldie Staines, MS, Nancy J. Petersen, PhD
Purpose Thumb basilar osteoarthritis is common. Several surgical options exist. Studies have evaluated outcomes in separate cohorts but have not compared methods. Our study compared the functional outcome of ligament reconstruction and tendon interposition (LRTI) suspension arthroplasty and hematoma distraction arthroplasty (HDA) by patient questionnaires, clinical measurements, and radiographic measurements to see whether there is validity in exclusively using either LRTI or HDA. Methods In this retrospective study, patients received LRTI (12 thumbs in 11 patients) or HDA (9 thumbs in 9 patients) according to the attending surgeon’s preference, one exclusively performing LRTI and the other HDA. Patient perception was evaluated with a QuickDASH questionnaire and 10-point pain visual analog scale (VAS). Potential QuickDASH scores range from 0 to 100, with lower scores indicating better function. Clinical evaluation examined grip strength, tip pinch, and lateral pinch in kilograms-force, and range of motion. Measurements were compared with those from the contralateral hand and published normal values. Stressed and unstressed radiographs assessed metacarpal proximal and lateral migration and first web space. Chart review documented surgical times. Results The LRTI and HDA scored similarly on QuickDASH. Most reported excellent pain relief. Average grip, tip pinch, and lateral pinch were also similar in both groups. None achieved significance. Comparisons with contralateral hand and published normal results showed that LRTI and HDA were comparable. All except 2 could oppose to little finger base. With stress, additional proximal migration was similar. Web space was preserved with both procedures. LRTI took 54 minutes longer. Conclusions The LRTI and HDA were comparable on all levels of objective and subjective measurements. Both groups satisfied the principal goals to provide a stable, mobile, pain-free thumb. (J Hand Surg 2010;35A:1968–1975. Copyright © 2010 by the American Society for Surgery of the Hand. All rights reserved.) Type of study/level of evidence Therapeutic III. Key words Arthroplasty, carpometacarpal, osteoarthritis, thumb, trapeziectomy.
From the Department of Orthopedic Surgery and Division of Plastic Surgery, Baylor College of Medicine, Houston, TX, Physcial Medicine and Rehabilitation Service, Michael E. DeBakey Veterans Affairs Medical Center, Houston, TX, and Biostatistics, Health Sciences Research and Development Center of Excellence, Michael E. DeBakey Department of Veterans Affairs Medical Center, Houston, TX. Received for publication December 9, 2009; accepted in revised form August 31, 2010. Statistical support was provided in part by the Houston VA HSR&D Center of Excellence (HFP90-020).
1968 䉬 © ASSH 䉬 Published by Elsevier, Inc. All rights reserved.
No benefits in any form have been received or will be received related directly or indirectly to the subject of this article. The views in this article are those of the authors and are not necessarily those of the Department of Veterans Affairs. Correspondingauthor:DavidT.Netscher,MD,6624FanninStreet,Suite2730,Houston,TX77030; e-mail: [email protected]. 0363-5023/10/35A12-0008$36.00/0 doi:10.1016/j.jhsa.2010.08.034
1969
BASAL JOINT OSTEOARTHRITIS
of the thumb is a common problem. Several surgical treatment options exist, although some techniques are more complex than others. Ligament reconstruction and tendon interposition (LRTI) suspension arthroplasty was described many years ago and continues to be one of the most frequently used techniques1,2; however, a simplified procedure, hematoma distraction arthroplasty (HDA), with decreased surgical time and potential cost savings, has been described.3 Both LRTI and HDA are popular surgical treatments, resulting in reportedly good functional outcomes and noteworthy pain relief.4,5 Previous studies have evaluated functional outcomes in separate cohorts.4,5 We sought to compare the 2 techniques using parameters similar to those used in previous studies—patient perception/ outcome questionnaires, strength, motion, and radiographic measurements. The purpose of our study was to compare the functional outcomes of the 2 groups by patient questionnaires and clinical measurements and to correlate potential functional outcome differences with radiographic measurements to see whether there is validity in exclusively using either LRTI or HDA for surgical treatment of carpometacarpal (CMC) joint osteoarthritis.
B
ASAL JOINT OSTEOARTHRITIS
MATERIALS AND METHODS Twenty-one thumbs of 20 patients were evaluated in this retrospective dual-cohort study at a mean follow-up interval of 24 months after surgery (range, 12 to 47 mo). We searched the computer database according to current procedural terminology codes for basal joint arthritis of the thumb. Patients were eligible if they received either an LRTI or an HDA at our hospital between 2005 and 2009. Two hand surgeons were the lead surgeons, and either performed or directly supervised all procedures. Patients received either LRTI or HDA according to the attending surgeon’s preference, with one attending surgeon exclusively performing LRTI and the other exclusively HDA. Standard procedures were performed as described by previous investigators.2– 4 A complete trapeziectomy was performed in all HDA procedures, and the flexor carpi radialis tendon was used for all LRTI basal joint arthroplasties. The LRTI group had 11 patients, and the HDA group had 9 patients. The average age at surgery and the follow-up interval were similar for both groups (Table 1). Patients were evaluated with standardized questionnaires, clinical examination, and radiographic examination. They were examined independent of the operating surgeon, and clinical measurements were performed by a certified hand therapist blinded to the procedure. Postoperative care was uniform for all, with cast immobilization for 3 weeks, followed by 3 weeks of immobili-
TABLE 1. Group Characteristics LRTI
HDA
Number of patients
11
9
Male/female
8/3
8/1
Number of thumbs
12
9
Dominant thumbs
4
4
Average age at surgery, y (range)
63 (44–74)
63 (51–86)
Average follow-up interval, mo (range)
29 (12–47)
22 (12–39)
zation in a molded plastic removable thumb spica, and then 6 to 9 weeks of supervised hand therapy to regain range of motion and strength. Patients gave appropriate informed consent about the objectives of the study. Patient questionnaires The QuickDASH questionnaire was used to assess ability to perform certain tasks.6 The questions asked about one’s ability to open a tight jar, perform heavy household chores, carry a shopping bag or briefcase, use a knife to cut food, participate in normal social and recreational activities, and perform regular daily activities. It also assessed pain and tingling, as well as difficulty sleeping because of pain in the arm, shoulder, or hand. Potential QuickDASH scores range from 0 to 100, with low values indicating better function. In addition to the QuickDASH questionnaire, patients completed a 10-point visual analog scale (VAS) to evaluate how much the hand hurts on a typical day, with low values indicating less pain. Clinical evaluation The physical examination measured strength and range of motion. Strength was evaluated by measuring bilateral grip strength, tip pinch, and lateral key pinch. Grip strength was measured using a Jamar dynamometer set at the second handle position (Asimov Engineering Co., Los Angeles, CA); pinch strength was measured using a B&L pinch gauge (B&L Engineering, Tustin, CA). Standard arm positioning was used.7 For each strength test, the scores of 3 successive trials were recorded; the highest value was used for analysis. Each of the 2 procedures was directly contrasted and also individually compared with both the contralateral nonsurgical hand and previously reported age-adjusted normal values.7 Standard measurements and values for grip and pinch strength in normal adults of different age ranges have previously been published.7 We used these as normal values for our comparisons because the opposite hand of our patients also was frequently affected by osteoarthritis. Range of motion was
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1970
BASAL JOINT OSTEOARTHRITIS
FIGURE 1: Calculating the trapezial space ratio. From a lateral thumb radiograph, the height of the trapezial space is divided by the length of the proximal phalanx to determine the trapezial space ratio both at rest and with tip pinch.
assessed by opposition of the tip of the thumb to an anatomic landmark on the small finger—either the tip of the small finger, the distal interphalangeal joint flexion crease, the proximal interphalangeal joint flexion crease, or the base of the small finger. Radiographic evaluation Several radiographs were taken of the affected hand to assess first metacarpal proximal and lateral migration, as well as the first web space. Radiographs were interpreted by a person blinded to the performed procedure. Proximal migration. To evaluate proximal migration, an anteroposterior (AP) wrist view (with true thumb lateral position) was used to calculate the trapezial space ratio, both at rest as well as with maximal-effort tip pinch. This ratio was calculated by dividing the height of the trapezial space by the length of the proximal phalanx, and it minimizes variability in the trapezial space attributable to varying hand size and standardizes for radiographic magnification8 (Fig. 1). These values were then compared with established normal values.8 Lateral migration. To assess lateral stability, we used both unstressed and stressed AP thumb radiographs. With the radial margins of the distal phalanx of each thumb pressed together, we calculated the percent of the base of the thumb metacarpal that extended over the lateral border of the longitudinal axis of the scaphoid4 (Fig. 2). First web space. The first web space was evaluated from
FIGURE 2: Calculating lateral migration. From an anteroposterior thumb radiograph with the radial margins of the distal phalanx of each thumb pressed together, the percent of the base of the thumb metacarpal that extends over the lateral border of the longitudinal axis of the scaphoid is measured.
a Robert view radiograph with the thumb in maximum palmar abduction. We measured the thumb-index intermetacarpal angle to evaluate thumb abduction and restoration of the first web space4 (Fig. 3). Contralateral hand. The AP and oblique radiographs of the contralateral hand were used to evaluate arthritic changes of the CMC joint. Surgical time Chart review documented surgical times. Statistical analysis Descriptive statistics (n, mean, standard deviation, and median) were calculated for questionnaires, clinical measurements, and radiographic measurements. The groups were compared using the nonparametric Wilcoxon 2-sample rank sum test. For all analyses, p values ⱕ.05 were considered statistically significant. RESULTS Patient questionnaires Results of patient questionnaires are shown in Table 2. The LRTI and HDA groups scored similarly on the QuickDASH and VAS (p ⫽ .52 and .83). One patient in the LRTI group suffered from reflex sympathetic dystrophy; although thumb reconstruction was satisfactory,
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1971
subsidence of 49% for the LRTI group and 50% for the HDA group when comparing postoperative trapezial space stress ratios to values obtained in normal thumbs. Overall, 11 thumbs (7 LRTI, 4 HDA) had no additional proximal migration of the metacarpal with stress. Five thumbs (4 LRTI, 1 HDA) migrated laterally when stressed; average percent lateral migration was greater in the LRTI group (Table 2). Overall, the first web space was well maintained, and the average thumbindex intermetacarpal angle was similar in both groups (Table 2). Contralateral CMC arthritis (Eaton and Littler stage II or greater) was seen in 5 of 12 thumbs in the LRTI group and 8 of 9 thumbs in the HDA group.
FIGURE 3: Calculating the first web space. From a Robert view radiograph, the thumb-index intermetacarpal angle is measured to evaluate restoration of the first web space.
his subjective evaluations did affect global hand function adversely, resulting in a substantially higher QuickDASH score (59) and VAS score (5.0) than the rest of the group. In spite of this, differences between the 2 groups were not statistically significant. Clinical evaluation Strength measurements are shown in Table 2. Average grip, tip pinch, and lateral key pinch strengths were similar in both groups (p ⫽ .21, .94, and .52, respectively). Both the LRTI and HDA groups regained a level of strength that more closely approximated strength in the contralateral hand (Fig. 4); however, this was not the case when compared with published normal values (Fig. 5). With regard to range of motion, all patients except 2 were able to oppose to the base of the small finger; the remaining patients could reach to the proximal interphalangeal joint flexion crease. Radiographic evaluation Proximal migration data, as measured by unstressed and stressed trapezial space ratios, are shown in Table 2, and percent decrease relative to normal is shown in Table 3. At rest, there was an average reduction in the trapezial space ratio of 28% in the LRTI group when compared with normal thumbs. In contrast, the HDA group had a reduction of 19%. With stress, both groups showed additional subsidence, 21% in the LRTI group and 31% in the HDA group. Thus, there was a total
Intergroup analysis Data for combined LRTI and HDA groups are shown in Table 4 to assess the impact of metacarpal migration on all patients. Radiographic measurements did not impact pain scores. When data for both groups were combined, lateral migration with stress was not associated with statistically significant differences for QuickDASH, grip strength, tip pinch, or lateral key pinch. Proximal migration with stress was associated with significantly better scores for QuickDASH (p ⫽ .03), grip strength (p ⫽ .01), and lateral key pinch (p ⫽ .01); tip pinch approached significance (p ⫽ .08). Surgical time Surgical times showed that on average the LRTI arthroplasty took 54 minutes longer than the HDA (Fig. 6). DISCUSSION The results of this study suggest that both LRTI and HDA are effective surgical treatments for basal joint osteoarthritis of the thumb. Both procedures met with a high degree of patient satisfaction. The goals were to provide a stable, mobile, and pain-free thumb, and this was achieved in both groups. In comparison with other published studies, we found the following. QuickDASH A potential complication with the LRTI technique, although not with HDA, is injury to the palmar cutaneous branch of the median nerve. Tingling is specifically addressed in the QuickDASH. Although not necessarily volunteering this information, each patient responded when prompted by the questionnaire. This particular question may account for the increase in the LRTI scores, as 6 of 12 patients in the LRTI group responded affirmatively to the question compared with only 2 of 9 in the HDA group. Bothersome paresthesias in the
JHS 䉬 Vol A, December
1972
TABLE 2.
BASAL JOINT OSTEOARTHRITIS
Average Measurements LRTI
HDA
p Value
20.5 ⫾ 15.8
17.7 ⫾ 19.0
.52
1.8 ⫾ 1.7
1.9 ⫾ 2.3
.83
22.1 ⫾ 9.6
29.3 ⫾ 14.7
.213
Questionnaires QuickDASH VAS Clinical measurements Grip strength (kg) Tip pinch (kg)
4.9 ⫾ 1.8
4.9 ⫾ 1.9
.943
Lateral key pinch (kg)
6.3 ⫾ 2.1
6.9 ⫾ 2.4
.5213
Unstressed trapezial space ratio
0.344 ⫾ 0.184
0.384 ⫾ 0.310
Stressed trapezial space ratio
0.244 ⫾ 0.085
0.237 ⫾ 0.103
.8311
6 ⫾ 13
1⫾4
.3177
49 ⫾ 9
.7486
Radiographic measurements
Percent lateral migration with stress
50 ⫾ 9
Web space (degrees)
95%
100% 86% 80%
1
84% 79%
78%
82%
60%
40%
20%
0% Grip Strength
Tip Pinch
Lateral Key Pinch
LRTI HDA
FIGURE 4: Percent of opposite hand.
palmar radial aspect of the thumb along the incision have been previously reported at 2-year follow-up examination; these completely resolved by the time of the 6- and 9-year evaluations.2,4
months of follow-up, most of our patients experienced noteworthy pain relief, with only mild pain on a daily basis; 7 of 20 patients (35%) reported complete pain relief.
VAS/Pain relief Previous long-term studies have reported high percentages of complete pain relief.4,5 At an average 24 months after HDA, 20 of 22 of patients (91%) were entirely pain free, and at 88 months after HDA, 18 of 22 patients (82%) experienced complete pain relief.3,5 In a 9-year follow-up evaluation, 20 of 22 patients (91%) had complete pain relief after LRTI.4 At an average 24
Strength At a 2-year follow-up evaluation of LRTI arthroplasties, grip strength was 17.6 kg, tip pinch 3.3 kg, and lateral pinch 4.4 kg.2 At 9 years of follow-up, they reported that grip strength and tip pinch had increased steadily for 6 years before reaching a plateau.4 At a 2-year follow-up of HDA patients, grip strength was 26 kg, tip pinch 6 kg, and lateral pinch 6 kg.4 At 7 years,
JHS 䉬 Vol A, December
1973
BASAL JOINT OSTEOARTHRITIS
100% 81% 80%
77% 72%
70%
70%
70%
60%
40%
20%
0% Grip Strength
Tip Pinch
Lateral Key Pinch
LRTI HDA
FIGURE 5: Percent of normal.
TABLE 3. Ratio
Percent Decrease in Trapezial Space LRTI
HDA
Unstressed vs normal
28%
19%
Stressed vs normal
49%
50%
Unstressed vs stressed
21%
31%
they reported that patients had a slight decrease in strength compared with the 2-year measurements.5 At an average of 2 years of follow-up, our LRTI and HDA cohorts had similar grip strength, tip pinch, and lateral key pinch to those previously reported4,5 (Table 5). Although average strength values in both of our groups were below the standard normal range (Fig. 5), one would not expect them to ever reach normal.2 Range of motion We found range of motion comparable with previously published long-term reports.4,5 Tomaino et al.4 reported no association between increased range of motion and decreased function or subluxation with stress. Proximal migration At long-term follow up, both Gray et al.5 and Tomaino et al.4 reported progressive proximal subsidence of the first metacarpal as well as additional subsidence with stress loading; both also reported that the decrease in height of the arthroplasty space did not correlate with clinical outcome. Gray et
al.5 reported that “continuing subsidence may raise concern about eventual symptomatic arthritis between the metacarpal and the scaphoid” and that a study with a longer follow-up period would be necessary to evaluate this.5 Lins et al.9 measured preoperative and 42-month postoperative LRTI unstressed trapezial space ratios. They reported a 51% decrease in the postoperative unstressed trapezial space ratio when compared with normal thumbs. Likewise, our LRTI group had an average decrease of 28% in the unstressed trapezial space ratio; with stress, there was additional subsidence. Lins et al.9 reported no correlation between postoperative trapezial space ratios and patient satisfaction, grip strength, lateral pinch strength, or ability to return to activities of daily living. Yang et al.10 reported on LRTIs at 32-month followup. They evaluated the effect of stress on the first metacarpal subsidence by calculating a ratio between the first metacarpal and the height of the arthroplasty space. They reported 21% subsidence at rest, which increased to 32% with stress and no statistical association between the subsidence and strength testing. Others have also reported no correlation between amount of subsidence and clinical outcome.11–13 One might speculate regarding why proximal migration in all patients was associated with better questionnaire scores and clinical measurements. This potentially may result from the inherent stability imparted by the pistoning of the metacarpal with stress loading as noted on radiographic measurements.
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1974
TABLE 4.
BASAL JOINT OSTEOARTHRITIS
Intergroup Analysis for All Patients to Assess Metacarpal Migration vs Clinical Outcome Lateral Migration
All Patients QuickDASH VAS
Yes
No
10.9 ⫾ 13.0 1.2 ⫾ 1.8
Proximal Migration p Value
Yes
No
p Value
21.9 ⫾ 17.4
.1458
13.4 ⫾ 18.0
24.6 ⫾ 14.4
.03ⴱ
2.1 ⫾ 2.0
.3506
1.8 ⫾ 2.4
1.9 ⫾ 1.5
.54
23.0 ⫾ 10.4
25.8 ⫾ 13.0
.6202
32.2 ⫾ 11.0
18.8 ⫾ 9.9
.01ⴱ
Tip pinch (kg)
5.2 ⫾ 1.8
4.9 ⫾ 1.8
.7087
5.6 ⫾ 1.4
4.3 ⫾ 1.9
.08
Lateral pinch (kg)
6.2 ⫾ 2.2
6.7 ⫾ 2.2
.7095
7.7 ⫾ 1.6
5.5 ⫾ 2.2
.01ⴱ
Grip strength (kg)
* Statistically significant, p ⬍ .05.
160
148
140
125
Minutes
120 100 100
84
80
71 52
60 40 20 0 Maximum
Minimum
Median
LRTI HDA
FIGURE 6: Surgical times.
TABLE 5.
Comparison of Strengths
Grip strength (kg)
Tomaino et al.2,4
Gray et al.3,5
LRTI
HDA
Our Study LRTI
HDA
After 24 mo
After 6 y
After 9 y
After 24 mo
After 7 y
After 24 mo
After 24 mo
17.6
24.4
24.6
26
23
22.1
29.3
Tip pinch (kg)
3.3
3.8
3.8
6
5
4.9
4.9
Lateral key pinch (kg)
4.4
5.6
4.9
6
5
6.3
6.9
Lateral migration In our patients, regardless of the reconstruction technique, proximal migration with stress loading seemed to result in improved strength measurements and questionnaire scores (Table 4). A long-term follow-up LRTI
study reported a stressed average subluxation of the base of the metacarpal of 7% at 2 years, 8% at 6 years, and 11% at 9 years, which was not predictive of unsatisfactory outcome.4 Our LRTI cohort had similar lateral migration. Most of the thumbs in our study had quite
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BASAL JOINT OSTEOARTHRITIS
good lateral stability, although more LRTI than HDA migrated laterally when stressed (4 LRTI, 1 HDA). First web space The average LRTI web angle at long-term follow-up was 40°, unchanged from the 2-year evaluation.4 Similar findings were noted for both groups in our study. Our study has some potential weaknesses. The sample was predominantly male and small in number, thus the power to find differences between groups was small. We had power of only 19% to detect a medium effect size of 0.50 (the difference in means between the 2 groups divided by their common standard deviation, which may be considered as a perceptible difference). Because our average follow-up interval was relatively short, we were not able to make a long-term comparison at this time. Continued improvement in strength has been demonstrated with LRTI arthroplasty.4 However, the longevity of HDA and its durability over time is unknown. Potential for increased proximal migration in the HDA group exists (Table 3) and is a concern that may eventually lead to a weaker thumb and pain from abutment on the distal scaphoid. A 6-year follow-up supports the durability of the HDA procedure, but there has not yet been a study with as long a follow-up interval as studies of LRTI.5 The retrospective design of our study precluded measurement of preoperative strength. Bilateral CMC osteoarthritis is quite prevalent, reported by others to be 20% to 30%, and 62% in our study. Thus, the contralateral hand is often weakened as well, limiting the utility of contralateral comparisons.2 However, strengths of our study include the direct comparison between 2 surgical techniques as well as the comprehensive clinical and radiographic evaluations. The LRTI arthroplasty is a considerably longer and more complex surgery than the HDA. When consider-
1975
ing the large number of CMC arthroplasties performed each year and the extra time and cost involved with the LRTI technique, there are substantial potential cost savings that could be realized by performing the shorter and less complex HDA procedure. REFERENCES 1. Burton RI. Thumb arthritis. In: Evarts CM, ed. Surgery of the musculoskeletal system. Vol 1. New York: Churchill Livingstone, 1983:670 – 681. 2. Burton RI, Pelligrini VD Jr. Surgical management of basal joint arthritis of the thumb. Part II. Ligament reconstruction with tendon interposition arthroplasty. J Hand Surg 1986;11A:324 –332. 3. Kuhns CA, Emerson ET, Meals RA. Hematoma and distraction arthroplasty for thumb basal joint osteoarthritis: a prospective, single-surgeon study including outcomes measures. J Hand Surg 2003; 28A:381–389. 4. Tomaino MM, Pelligrini VD Jr, Burton RI. Arthroplasty of the basal joint of the thumb. Long-term follow-up after ligament reconstruction with tendon interposition. J Bone Joint Surg 1995;77A:346 – 355. 5. Gray KV, Meals RA. Hematoma and distraction arthroplasty for thumb basal joint osteoarthritis: minimum 6.5-year follow-up evaluation. J Hand Surg 2007;32A:23–29. 6. Beaton DE, Wright JG, Katz JN, Upper Extremity Collaborative Group. Development of the QuickDASH: comparison of three itemreduction approaches. J Bone Joint Surg 2005;87A:1038 –1046. 7. Mathiowetz V, Kashman N, Volland G, Weber K, Dowe M, Rogers S. Grip and pinch strength: normative data for adults. Arch Phys Med Rehabil 1985;66:69 –74. 8. Kadiyala RK, Gelberman RH, Kwon B. Radiographic assessment of the trapezial space before and after ligament reconstruction and tendon interposition arthroplasty. J Hand Surg 1996;21B:2:177–181. 9. Lins RE, Gelberman RH, McKeown L, Katz JN, Kadiyala RK. Basal joint arthritis: trapeziectomy with ligament reconstruction and tendon interposition arthroplasty. J Hand Surg 1996;21A:202–209. 10. Yang SS, Weiland AJ. First metacarpal subsidence during pinch after ligament reconstruction and tendon interposition basal joint arthroplasty of the thumb. J Hand Surg 1998;23A:879 – 883. 11. Rayan GM, Young BT. Ligament reconstruction arthroplasty for trapeziometacarpal arthrosis. J Hand Surg 1997;22A:1067–1076. 12. Dell PC, Muniz RB. Interposition arthroplasty of the trapeziometacarpal joint for osteoarthritis. Clin Orthop 1987;220:27–34. 13. Downing ND, Davis TR. Trapezial space height after trapeziectomy: mechanism of formation and benefits. J Hand Surg 2001;26A:862– 868.
JHS 䉬 Vol A, December
Basal Joint Osteoarthritis of the Thumb: Ligament Reconstruction and Tendon Interposition Versus Hematoma Distraction Arthroplasty Brinkley K. Sandvall, BS, Todd E. Cameron, DO, David T. Netscher, MD, Michael J. Epstein, MD, Kimberly Goldie Staines, MS, Nancy J. Petersen, PhD
Purpose Thumb basilar osteoarthritis is common. Several surgical options exist. Studies have evaluated outcomes in separate cohorts but have not compared methods. Our study compared the functional outcome of ligament reconstruction and tendon interposition (LRTI) suspension arthroplasty and hematoma distraction arthroplasty (HDA) by patient questionnaires, clinical measurements, and radiographic measurements to see whether there is validity in exclusively using either LRTI or HDA. Methods In this retrospective study, patients received LRTI (12 thumbs in 11 patients) or HDA (9 thumbs in 9 patients) according to the attending surgeon’s preference, one exclusively performing LRTI and the other HDA. Patient perception was evaluated with a QuickDASH questionnaire and 10-point pain visual analog scale (VAS). Potential QuickDASH scores range from 0 to 100, with lower scores indicating better function. Clinical evaluation examined grip strength, tip pinch, and lateral pinch in kilograms-force, and range of motion. Measurements were compared with those from the contralateral hand and published normal values. Stressed and unstressed radiographs assessed metacarpal proximal and lateral migration and first web space. Chart review documented surgical times. Results The LRTI and HDA scored similarly on QuickDASH. Most reported excellent pain relief. Average grip, tip pinch, and lateral pinch were also similar in both groups. None achieved significance. Comparisons with contralateral hand and published normal results showed that LRTI and HDA were comparable. All except 2 could oppose to little finger base. With stress, additional proximal migration was similar. Web space was preserved with both procedures. LRTI took 54 minutes longer. Conclusions The LRTI and HDA were comparable on all levels of objective and subjective measurements. Both groups satisfied the principal goals to provide a stable, mobile, pain-free thumb. (J Hand Surg 2010;35A:1968–1975. Copyright © 2010 by the American Society for Surgery of the Hand. All rights reserved.) Type of study/level of evidence Therapeutic III. Key words Arthroplasty, carpometacarpal, osteoarthritis, thumb, trapeziectomy.
From the Department of Orthopedic Surgery and Division of Plastic Surgery, Baylor College of Medicine, Houston, TX, Physcial Medicine and Rehabilitation Service, Michael E. DeBakey Veterans Affairs Medical Center, Houston, TX, and Biostatistics, Health Sciences Research and Development Center of Excellence, Michael E. DeBakey Department of Veterans Affairs Medical Center, Houston, TX. Received for publication December 9, 2009; accepted in revised form August 31, 2010. Statistical support was provided in part by the Houston VA HSR&D Center of Excellence (HFP90-020).
1968 䉬 © ASSH 䉬 Published by Elsevier, Inc. All rights reserved.
No benefits in any form have been received or will be received related directly or indirectly to the subject of this article. The views in this article are those of the authors and are not necessarily those of the Department of Veterans Affairs. Correspondingauthor:DavidT.Netscher,MD,6624FanninStreet,Suite2730,Houston,TX77030; e-mail: [email protected]. 0363-5023/10/35A12-0008$36.00/0 doi:10.1016/j.jhsa.2010.08.034
1969
BASAL JOINT OSTEOARTHRITIS
of the thumb is a common problem. Several surgical treatment options exist, although some techniques are more complex than others. Ligament reconstruction and tendon interposition (LRTI) suspension arthroplasty was described many years ago and continues to be one of the most frequently used techniques1,2; however, a simplified procedure, hematoma distraction arthroplasty (HDA), with decreased surgical time and potential cost savings, has been described.3 Both LRTI and HDA are popular surgical treatments, resulting in reportedly good functional outcomes and noteworthy pain relief.4,5 Previous studies have evaluated functional outcomes in separate cohorts.4,5 We sought to compare the 2 techniques using parameters similar to those used in previous studies—patient perception/ outcome questionnaires, strength, motion, and radiographic measurements. The purpose of our study was to compare the functional outcomes of the 2 groups by patient questionnaires and clinical measurements and to correlate potential functional outcome differences with radiographic measurements to see whether there is validity in exclusively using either LRTI or HDA for surgical treatment of carpometacarpal (CMC) joint osteoarthritis.
B
ASAL JOINT OSTEOARTHRITIS
MATERIALS AND METHODS Twenty-one thumbs of 20 patients were evaluated in this retrospective dual-cohort study at a mean follow-up interval of 24 months after surgery (range, 12 to 47 mo). We searched the computer database according to current procedural terminology codes for basal joint arthritis of the thumb. Patients were eligible if they received either an LRTI or an HDA at our hospital between 2005 and 2009. Two hand surgeons were the lead surgeons, and either performed or directly supervised all procedures. Patients received either LRTI or HDA according to the attending surgeon’s preference, with one attending surgeon exclusively performing LRTI and the other exclusively HDA. Standard procedures were performed as described by previous investigators.2– 4 A complete trapeziectomy was performed in all HDA procedures, and the flexor carpi radialis tendon was used for all LRTI basal joint arthroplasties. The LRTI group had 11 patients, and the HDA group had 9 patients. The average age at surgery and the follow-up interval were similar for both groups (Table 1). Patients were evaluated with standardized questionnaires, clinical examination, and radiographic examination. They were examined independent of the operating surgeon, and clinical measurements were performed by a certified hand therapist blinded to the procedure. Postoperative care was uniform for all, with cast immobilization for 3 weeks, followed by 3 weeks of immobili-
TABLE 1. Group Characteristics LRTI
HDA
Number of patients
11
9
Male/female
8/3
8/1
Number of thumbs
12
9
Dominant thumbs
4
4
Average age at surgery, y (range)
63 (44–74)
63 (51–86)
Average follow-up interval, mo (range)
29 (12–47)
22 (12–39)
zation in a molded plastic removable thumb spica, and then 6 to 9 weeks of supervised hand therapy to regain range of motion and strength. Patients gave appropriate informed consent about the objectives of the study. Patient questionnaires The QuickDASH questionnaire was used to assess ability to perform certain tasks.6 The questions asked about one’s ability to open a tight jar, perform heavy household chores, carry a shopping bag or briefcase, use a knife to cut food, participate in normal social and recreational activities, and perform regular daily activities. It also assessed pain and tingling, as well as difficulty sleeping because of pain in the arm, shoulder, or hand. Potential QuickDASH scores range from 0 to 100, with low values indicating better function. In addition to the QuickDASH questionnaire, patients completed a 10-point visual analog scale (VAS) to evaluate how much the hand hurts on a typical day, with low values indicating less pain. Clinical evaluation The physical examination measured strength and range of motion. Strength was evaluated by measuring bilateral grip strength, tip pinch, and lateral key pinch. Grip strength was measured using a Jamar dynamometer set at the second handle position (Asimov Engineering Co., Los Angeles, CA); pinch strength was measured using a B&L pinch gauge (B&L Engineering, Tustin, CA). Standard arm positioning was used.7 For each strength test, the scores of 3 successive trials were recorded; the highest value was used for analysis. Each of the 2 procedures was directly contrasted and also individually compared with both the contralateral nonsurgical hand and previously reported age-adjusted normal values.7 Standard measurements and values for grip and pinch strength in normal adults of different age ranges have previously been published.7 We used these as normal values for our comparisons because the opposite hand of our patients also was frequently affected by osteoarthritis. Range of motion was
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1970
BASAL JOINT OSTEOARTHRITIS
FIGURE 1: Calculating the trapezial space ratio. From a lateral thumb radiograph, the height of the trapezial space is divided by the length of the proximal phalanx to determine the trapezial space ratio both at rest and with tip pinch.
assessed by opposition of the tip of the thumb to an anatomic landmark on the small finger—either the tip of the small finger, the distal interphalangeal joint flexion crease, the proximal interphalangeal joint flexion crease, or the base of the small finger. Radiographic evaluation Several radiographs were taken of the affected hand to assess first metacarpal proximal and lateral migration, as well as the first web space. Radiographs were interpreted by a person blinded to the performed procedure. Proximal migration. To evaluate proximal migration, an anteroposterior (AP) wrist view (with true thumb lateral position) was used to calculate the trapezial space ratio, both at rest as well as with maximal-effort tip pinch. This ratio was calculated by dividing the height of the trapezial space by the length of the proximal phalanx, and it minimizes variability in the trapezial space attributable to varying hand size and standardizes for radiographic magnification8 (Fig. 1). These values were then compared with established normal values.8 Lateral migration. To assess lateral stability, we used both unstressed and stressed AP thumb radiographs. With the radial margins of the distal phalanx of each thumb pressed together, we calculated the percent of the base of the thumb metacarpal that extended over the lateral border of the longitudinal axis of the scaphoid4 (Fig. 2). First web space. The first web space was evaluated from
FIGURE 2: Calculating lateral migration. From an anteroposterior thumb radiograph with the radial margins of the distal phalanx of each thumb pressed together, the percent of the base of the thumb metacarpal that extends over the lateral border of the longitudinal axis of the scaphoid is measured.
a Robert view radiograph with the thumb in maximum palmar abduction. We measured the thumb-index intermetacarpal angle to evaluate thumb abduction and restoration of the first web space4 (Fig. 3). Contralateral hand. The AP and oblique radiographs of the contralateral hand were used to evaluate arthritic changes of the CMC joint. Surgical time Chart review documented surgical times. Statistical analysis Descriptive statistics (n, mean, standard deviation, and median) were calculated for questionnaires, clinical measurements, and radiographic measurements. The groups were compared using the nonparametric Wilcoxon 2-sample rank sum test. For all analyses, p values ⱕ.05 were considered statistically significant. RESULTS Patient questionnaires Results of patient questionnaires are shown in Table 2. The LRTI and HDA groups scored similarly on the QuickDASH and VAS (p ⫽ .52 and .83). One patient in the LRTI group suffered from reflex sympathetic dystrophy; although thumb reconstruction was satisfactory,
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1971
subsidence of 49% for the LRTI group and 50% for the HDA group when comparing postoperative trapezial space stress ratios to values obtained in normal thumbs. Overall, 11 thumbs (7 LRTI, 4 HDA) had no additional proximal migration of the metacarpal with stress. Five thumbs (4 LRTI, 1 HDA) migrated laterally when stressed; average percent lateral migration was greater in the LRTI group (Table 2). Overall, the first web space was well maintained, and the average thumbindex intermetacarpal angle was similar in both groups (Table 2). Contralateral CMC arthritis (Eaton and Littler stage II or greater) was seen in 5 of 12 thumbs in the LRTI group and 8 of 9 thumbs in the HDA group.
FIGURE 3: Calculating the first web space. From a Robert view radiograph, the thumb-index intermetacarpal angle is measured to evaluate restoration of the first web space.
his subjective evaluations did affect global hand function adversely, resulting in a substantially higher QuickDASH score (59) and VAS score (5.0) than the rest of the group. In spite of this, differences between the 2 groups were not statistically significant. Clinical evaluation Strength measurements are shown in Table 2. Average grip, tip pinch, and lateral key pinch strengths were similar in both groups (p ⫽ .21, .94, and .52, respectively). Both the LRTI and HDA groups regained a level of strength that more closely approximated strength in the contralateral hand (Fig. 4); however, this was not the case when compared with published normal values (Fig. 5). With regard to range of motion, all patients except 2 were able to oppose to the base of the small finger; the remaining patients could reach to the proximal interphalangeal joint flexion crease. Radiographic evaluation Proximal migration data, as measured by unstressed and stressed trapezial space ratios, are shown in Table 2, and percent decrease relative to normal is shown in Table 3. At rest, there was an average reduction in the trapezial space ratio of 28% in the LRTI group when compared with normal thumbs. In contrast, the HDA group had a reduction of 19%. With stress, both groups showed additional subsidence, 21% in the LRTI group and 31% in the HDA group. Thus, there was a total
Intergroup analysis Data for combined LRTI and HDA groups are shown in Table 4 to assess the impact of metacarpal migration on all patients. Radiographic measurements did not impact pain scores. When data for both groups were combined, lateral migration with stress was not associated with statistically significant differences for QuickDASH, grip strength, tip pinch, or lateral key pinch. Proximal migration with stress was associated with significantly better scores for QuickDASH (p ⫽ .03), grip strength (p ⫽ .01), and lateral key pinch (p ⫽ .01); tip pinch approached significance (p ⫽ .08). Surgical time Surgical times showed that on average the LRTI arthroplasty took 54 minutes longer than the HDA (Fig. 6). DISCUSSION The results of this study suggest that both LRTI and HDA are effective surgical treatments for basal joint osteoarthritis of the thumb. Both procedures met with a high degree of patient satisfaction. The goals were to provide a stable, mobile, and pain-free thumb, and this was achieved in both groups. In comparison with other published studies, we found the following. QuickDASH A potential complication with the LRTI technique, although not with HDA, is injury to the palmar cutaneous branch of the median nerve. Tingling is specifically addressed in the QuickDASH. Although not necessarily volunteering this information, each patient responded when prompted by the questionnaire. This particular question may account for the increase in the LRTI scores, as 6 of 12 patients in the LRTI group responded affirmatively to the question compared with only 2 of 9 in the HDA group. Bothersome paresthesias in the
JHS 䉬 Vol A, December
1972
TABLE 2.
BASAL JOINT OSTEOARTHRITIS
Average Measurements LRTI
HDA
p Value
20.5 ⫾ 15.8
17.7 ⫾ 19.0
.52
1.8 ⫾ 1.7
1.9 ⫾ 2.3
.83
22.1 ⫾ 9.6
29.3 ⫾ 14.7
.213
Questionnaires QuickDASH VAS Clinical measurements Grip strength (kg) Tip pinch (kg)
4.9 ⫾ 1.8
4.9 ⫾ 1.9
.943
Lateral key pinch (kg)
6.3 ⫾ 2.1
6.9 ⫾ 2.4
.5213
Unstressed trapezial space ratio
0.344 ⫾ 0.184
0.384 ⫾ 0.310
Stressed trapezial space ratio
0.244 ⫾ 0.085
0.237 ⫾ 0.103
.8311
6 ⫾ 13
1⫾4
.3177
49 ⫾ 9
.7486
Radiographic measurements
Percent lateral migration with stress
50 ⫾ 9
Web space (degrees)
95%
100% 86% 80%
1
84% 79%
78%
82%
60%
40%
20%
0% Grip Strength
Tip Pinch
Lateral Key Pinch
LRTI HDA
FIGURE 4: Percent of opposite hand.
palmar radial aspect of the thumb along the incision have been previously reported at 2-year follow-up examination; these completely resolved by the time of the 6- and 9-year evaluations.2,4
months of follow-up, most of our patients experienced noteworthy pain relief, with only mild pain on a daily basis; 7 of 20 patients (35%) reported complete pain relief.
VAS/Pain relief Previous long-term studies have reported high percentages of complete pain relief.4,5 At an average 24 months after HDA, 20 of 22 of patients (91%) were entirely pain free, and at 88 months after HDA, 18 of 22 patients (82%) experienced complete pain relief.3,5 In a 9-year follow-up evaluation, 20 of 22 patients (91%) had complete pain relief after LRTI.4 At an average 24
Strength At a 2-year follow-up evaluation of LRTI arthroplasties, grip strength was 17.6 kg, tip pinch 3.3 kg, and lateral pinch 4.4 kg.2 At 9 years of follow-up, they reported that grip strength and tip pinch had increased steadily for 6 years before reaching a plateau.4 At a 2-year follow-up of HDA patients, grip strength was 26 kg, tip pinch 6 kg, and lateral pinch 6 kg.4 At 7 years,
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BASAL JOINT OSTEOARTHRITIS
100% 81% 80%
77% 72%
70%
70%
70%
60%
40%
20%
0% Grip Strength
Tip Pinch
Lateral Key Pinch
LRTI HDA
FIGURE 5: Percent of normal.
TABLE 3. Ratio
Percent Decrease in Trapezial Space LRTI
HDA
Unstressed vs normal
28%
19%
Stressed vs normal
49%
50%
Unstressed vs stressed
21%
31%
they reported that patients had a slight decrease in strength compared with the 2-year measurements.5 At an average of 2 years of follow-up, our LRTI and HDA cohorts had similar grip strength, tip pinch, and lateral key pinch to those previously reported4,5 (Table 5). Although average strength values in both of our groups were below the standard normal range (Fig. 5), one would not expect them to ever reach normal.2 Range of motion We found range of motion comparable with previously published long-term reports.4,5 Tomaino et al.4 reported no association between increased range of motion and decreased function or subluxation with stress. Proximal migration At long-term follow up, both Gray et al.5 and Tomaino et al.4 reported progressive proximal subsidence of the first metacarpal as well as additional subsidence with stress loading; both also reported that the decrease in height of the arthroplasty space did not correlate with clinical outcome. Gray et
al.5 reported that “continuing subsidence may raise concern about eventual symptomatic arthritis between the metacarpal and the scaphoid” and that a study with a longer follow-up period would be necessary to evaluate this.5 Lins et al.9 measured preoperative and 42-month postoperative LRTI unstressed trapezial space ratios. They reported a 51% decrease in the postoperative unstressed trapezial space ratio when compared with normal thumbs. Likewise, our LRTI group had an average decrease of 28% in the unstressed trapezial space ratio; with stress, there was additional subsidence. Lins et al.9 reported no correlation between postoperative trapezial space ratios and patient satisfaction, grip strength, lateral pinch strength, or ability to return to activities of daily living. Yang et al.10 reported on LRTIs at 32-month followup. They evaluated the effect of stress on the first metacarpal subsidence by calculating a ratio between the first metacarpal and the height of the arthroplasty space. They reported 21% subsidence at rest, which increased to 32% with stress and no statistical association between the subsidence and strength testing. Others have also reported no correlation between amount of subsidence and clinical outcome.11–13 One might speculate regarding why proximal migration in all patients was associated with better questionnaire scores and clinical measurements. This potentially may result from the inherent stability imparted by the pistoning of the metacarpal with stress loading as noted on radiographic measurements.
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1974
TABLE 4.
BASAL JOINT OSTEOARTHRITIS
Intergroup Analysis for All Patients to Assess Metacarpal Migration vs Clinical Outcome Lateral Migration
All Patients QuickDASH VAS
Yes
No
10.9 ⫾ 13.0 1.2 ⫾ 1.8
Proximal Migration p Value
Yes
No
p Value
21.9 ⫾ 17.4
.1458
13.4 ⫾ 18.0
24.6 ⫾ 14.4
.03ⴱ
2.1 ⫾ 2.0
.3506
1.8 ⫾ 2.4
1.9 ⫾ 1.5
.54
23.0 ⫾ 10.4
25.8 ⫾ 13.0
.6202
32.2 ⫾ 11.0
18.8 ⫾ 9.9
.01ⴱ
Tip pinch (kg)
5.2 ⫾ 1.8
4.9 ⫾ 1.8
.7087
5.6 ⫾ 1.4
4.3 ⫾ 1.9
.08
Lateral pinch (kg)
6.2 ⫾ 2.2
6.7 ⫾ 2.2
.7095
7.7 ⫾ 1.6
5.5 ⫾ 2.2
.01ⴱ
Grip strength (kg)
* Statistically significant, p ⬍ .05.
160
148
140
125
Minutes
120 100 100
84
80
71 52
60 40 20 0 Maximum
Minimum
Median
LRTI HDA
FIGURE 6: Surgical times.
TABLE 5.
Comparison of Strengths
Grip strength (kg)
Tomaino et al.2,4
Gray et al.3,5
LRTI
HDA
Our Study LRTI
HDA
After 24 mo
After 6 y
After 9 y
After 24 mo
After 7 y
After 24 mo
After 24 mo
17.6
24.4
24.6
26
23
22.1
29.3
Tip pinch (kg)
3.3
3.8
3.8
6
5
4.9
4.9
Lateral key pinch (kg)
4.4
5.6
4.9
6
5
6.3
6.9
Lateral migration In our patients, regardless of the reconstruction technique, proximal migration with stress loading seemed to result in improved strength measurements and questionnaire scores (Table 4). A long-term follow-up LRTI
study reported a stressed average subluxation of the base of the metacarpal of 7% at 2 years, 8% at 6 years, and 11% at 9 years, which was not predictive of unsatisfactory outcome.4 Our LRTI cohort had similar lateral migration. Most of the thumbs in our study had quite
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BASAL JOINT OSTEOARTHRITIS
good lateral stability, although more LRTI than HDA migrated laterally when stressed (4 LRTI, 1 HDA). First web space The average LRTI web angle at long-term follow-up was 40°, unchanged from the 2-year evaluation.4 Similar findings were noted for both groups in our study. Our study has some potential weaknesses. The sample was predominantly male and small in number, thus the power to find differences between groups was small. We had power of only 19% to detect a medium effect size of 0.50 (the difference in means between the 2 groups divided by their common standard deviation, which may be considered as a perceptible difference). Because our average follow-up interval was relatively short, we were not able to make a long-term comparison at this time. Continued improvement in strength has been demonstrated with LRTI arthroplasty.4 However, the longevity of HDA and its durability over time is unknown. Potential for increased proximal migration in the HDA group exists (Table 3) and is a concern that may eventually lead to a weaker thumb and pain from abutment on the distal scaphoid. A 6-year follow-up supports the durability of the HDA procedure, but there has not yet been a study with as long a follow-up interval as studies of LRTI.5 The retrospective design of our study precluded measurement of preoperative strength. Bilateral CMC osteoarthritis is quite prevalent, reported by others to be 20% to 30%, and 62% in our study. Thus, the contralateral hand is often weakened as well, limiting the utility of contralateral comparisons.2 However, strengths of our study include the direct comparison between 2 surgical techniques as well as the comprehensive clinical and radiographic evaluations. The LRTI arthroplasty is a considerably longer and more complex surgery than the HDA. When consider-
1975
ing the large number of CMC arthroplasties performed each year and the extra time and cost involved with the LRTI technique, there are substantial potential cost savings that could be realized by performing the shorter and less complex HDA procedure. REFERENCES 1. Burton RI. Thumb arthritis. In: Evarts CM, ed. Surgery of the musculoskeletal system. Vol 1. New York: Churchill Livingstone, 1983:670 – 681. 2. Burton RI, Pelligrini VD Jr. Surgical management of basal joint arthritis of the thumb. Part II. Ligament reconstruction with tendon interposition arthroplasty. J Hand Surg 1986;11A:324 –332. 3. Kuhns CA, Emerson ET, Meals RA. Hematoma and distraction arthroplasty for thumb basal joint osteoarthritis: a prospective, single-surgeon study including outcomes measures. J Hand Surg 2003; 28A:381–389. 4. Tomaino MM, Pelligrini VD Jr, Burton RI. Arthroplasty of the basal joint of the thumb. Long-term follow-up after ligament reconstruction with tendon interposition. J Bone Joint Surg 1995;77A:346 – 355. 5. Gray KV, Meals RA. Hematoma and distraction arthroplasty for thumb basal joint osteoarthritis: minimum 6.5-year follow-up evaluation. J Hand Surg 2007;32A:23–29. 6. Beaton DE, Wright JG, Katz JN, Upper Extremity Collaborative Group. Development of the QuickDASH: comparison of three itemreduction approaches. J Bone Joint Surg 2005;87A:1038 –1046. 7. Mathiowetz V, Kashman N, Volland G, Weber K, Dowe M, Rogers S. Grip and pinch strength: normative data for adults. Arch Phys Med Rehabil 1985;66:69 –74. 8. Kadiyala RK, Gelberman RH, Kwon B. Radiographic assessment of the trapezial space before and after ligament reconstruction and tendon interposition arthroplasty. J Hand Surg 1996;21B:2:177–181. 9. Lins RE, Gelberman RH, McKeown L, Katz JN, Kadiyala RK. Basal joint arthritis: trapeziectomy with ligament reconstruction and tendon interposition arthroplasty. J Hand Surg 1996;21A:202–209. 10. Yang SS, Weiland AJ. First metacarpal subsidence during pinch after ligament reconstruction and tendon interposition basal joint arthroplasty of the thumb. J Hand Surg 1998;23A:879 – 883. 11. Rayan GM, Young BT. Ligament reconstruction arthroplasty for trapeziometacarpal arthrosis. J Hand Surg 1997;22A:1067–1076. 12. Dell PC, Muniz RB. Interposition arthroplasty of the trapeziometacarpal joint for osteoarthritis. Clin Orthop 1987;220:27–34. 13. Downing ND, Davis TR. Trapezial space height after trapeziectomy: mechanism of formation and benefits. J Hand Surg 2001;26A:862– 868.
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