Outcomes of Endoscopic Carpal Tunnel Release Surgery With Home Guided Hand Therapy Versus No Hand Therapy: A Prospective Randomized Controlled Trial After Endoscopic Carpal Tunnel Release

Abstract

Background:

The most recent American Academy of Orthopaedic Surgeons Clinical Practice Guidelines found no high-quality evidence comparing home therapy to no therapy following carpal tunnel release surgery (CTRS). Therefore, this study’s purpose is to compare the outcomes of patients receiving home therapy and patients receiving no therapy following endoscopic CTRS.

Methods:

A single-blinded prospective randomized controlled trial was performed. Patients were randomized to receive home hand therapy or no therapy postoperatively. Patients were assessed at baseline, 2, 6, and 12 weeks postoperatively. Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH) scores and Boston Carpal Tunnel Questionnaire (BCTQ) scores were evaluated as primary outcome measures. Grip strength, pinch strength, numerical pain rating scale (NRS), static 2-point discrimination, and hand circumference were also measured.

Results:

Fifty patients were randomized to home therapy while 55 patients were randomized to no therapy. The QuickDASH, BCTQ functional status scale (FSS), and BCTQ symptom severity scale (SSS) improved over time in both treatment groups. As-treated and intention-to-treat analysis showed no difference in improvement of QuickDASH, BCTQ FSS, or BCTQ SSS between treatment groups. Additionally, there was no significant difference between treatment groups in grip strength, chuck and key strength, NRS, hand circumference, and static 2-point discrimination.

Conclusions:

This blinded, prospective randomized controlled study shows no significant difference in improvement of QuickDASH, BCTQ SSS, and BCTQ FSS scores between patients receiving no therapy and home therapy following endoscopic CTRS. Consideration should be given to releasing patients without supervised therapy in the postoperative setting.

Level of Evidence:

Level II Therapeutic

Introduction

Carpal tunnel syndrome (CTS) is a common musculoskeletal condition that can severely affect a patients’ livelihood. Caused by increased pressure within the carpal tunnel that compresses the median nerve, ¹ CTS reportedly impacts 3% to 6% of American adults and up to 8% of the “working population.” ² Physicians often utilize conservative treatments initially to help control patient symptoms. Unfortunately, these methods, including therapeutic ultrasound, splinting, exercise prescription, mobilization techniques, ergonomic modification, oral medication, and corticosteroid injections, have not been shown to have much therapeutic benefit.^3,4

If conservative interventions fail, patients and surgeons often utilize carpal tunnel release surgery (CTRS) to alleviate patient symptoms and functional deficits. Many studies exist comparing the open approach, “mini-open” approach, and endoscopic approach to CTR.^{5 -9} Postoperatively, studies have shown that early mobilization helps patients achieve improved functional outcomes.^10,11 Various postoperative formal rehabilitation protocols have been described aimed at expediting recovery by improving mobility, strengthening the hand, and controlling postoperative swelling and pain.^{12 -14} However, there is continued debate whether these protocols are beneficial.

The most recent American Academy of Orthopaedic Surgeons Clinical Practice Guidelines (AAOS CPG) found moderate evidence to support no additional benefit of routine supervised therapy over home programs following CTR. ¹ However, the literature is scarce on the benefit of home hand therapy compared to no therapy in the rehabilitation process after CTR. Our study compares a formal home hand therapy program to no therapy postoperatively after endoscopic CTR, exploring whether formal hand therapy improves functional outcomes postoperatively. We hypothesize home hand therapy provides minimal benefit to patients compared to no therapy.

Materials and Methods

Approval for this single-blinded, randomized controlled trial was obtained from our hospital Institutional Review Board. Over a 12-month period, all subjects older than 18 years of age with symptoms of CTS who had previously failed conservative management were included. No patients initially declined to participate in the study. Patients who underwent previous carpal tunnel surgery or bilateral carpal tunnel surgery or were worker’s compensation cases were excluded. All patients were diagnosed clinically with a history, physical examination, and utilization of a CTS-6 score, with electrodiagnostic studies only used to confirm the diagnosis in equivocal scenarios. Surgical release was performed via a double portal endoscopic carpal tunnel release in the operating room by one blinded, fellowship trained orthopedic hand surgeon at a single suburban orthopedic center. All surgeries were performed in a community hospital on an outpatient basis using either only local anesthesia (20 mL of 1% lidocaine with 1:100 000 epinephrine) or a combination of local anesthesia with conscious sedation per patient preference.

Prior to surgery, patients were randomly enrolled into 2 groups using a random number generator that corresponded to sealed envelopes dictating treatment group. One group consisted of no formal postoperative hand therapy while the other group received detailed instruction on home exercises to be performed daily starting the day following surgery. Patients randomized to the no therapy group were instructed to perform activities and range of motion to their tolerance while being restricted to a 5-pound weight limit until the sutures were removed (to start the day following surgery). Both groups had their therapy instructions described in detail by the orthopedic hand surgeon and physical therapist in the clinic (online Appendix 1) depicting distal interphalangeal joint (DIP) and proximal interphalangeal joint (PIP) blocking exercises, as well as tendon and median nerve gliding exercises to be performed daily following surgery, while still being allowed to perform activities and range of motion to their tolerance and adhering to the same 5-pound weight limit until suture removal. Therapy instructions included performing 10 repetitions of each exercise 4 times daily.

For each patient, Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH) and Boston Carpal Tunnel Questionnaire (BCTQ) functional status scale (FSS) and symptom severity scale (SSS) were recorded to evaluate primary clinical outcomes. Numerical pain rating scale (NRS), grip strength, chuck and key pinch strength, hand circumference and static 2-point discrimination were also recorded. Individuals blinded to the patients’ treatment group collected all data. Preoperative baseline values and postoperative outcomes were collected at approximately 2-week, 6-week, and 12-week clinic visits. If patients did not return for their scheduled postoperative visits, patients were contacted by telephone within 1 to 2 weeks of their scheduled visit. Numerical pain rating scale was defined as a value between 0 and 10 with a score of zero corresponding to no pain and a score of 10 corresponding to severe pain.

Grip strength was evaluated using a Jamar hand dynamometer at position II (Prohealthcare Products, Utah). Pinch strength was evaluated using a Baseline Mechanical Pinch Gauge (Prohealthcare Products). Static 2-point discrimination was evaluated using a Dellon-McKinnon Disk-Criminator (US Neurologicals, Washington) at the thumb, index, and small finger. Patients who did not complete in-office follow-up were contacted via telephone and only NRS, QuickDASH scores, and BCTQ scores were obtained. For those patients that did not complete all follow-up visits, the remaining data were analyzed using both an “as-treated” and “intention-to-treat” analysis in addition to the last value carried forward technique in order to draw more robust conclusions and to account for patients lost to follow-up within a randomized controlled trial [13]. Data were analyzed using descriptive statistics, student’s t-test, one-way analysis of variance (ANOVA), and mixed ANOVA as appropriate to determine associations. For all analyses, P ≤ .05 denotes statistical significance.

Results

A total of 105 patients were initially enrolled in the study, with 50 randomized to home therapy and 55 to no therapy. A sample size was calculated using QuickDASH as the primary outcome which yielded a sample size of 45 patients per group (90 total patients) using a power of 80% with a 0.05 significance. There was no significant difference in age between the 2 groups (56 vs. 59) with patient demographics demonstrated in Table 1. Within the designated home therapy cohort, 42 patients ultimately proceeded to surgery, while 48 patients randomized to no therapy received surgery. Multiple patients initially enrolled did not ultimately proceed to surgery for a variety of reasons including insurance authorization, work schedule, and the desire to continue with conservative management. No patients crossed over between treatment groups. No patients experienced complications requiring a return to the operating room. There was no significant difference in days to return to work between employed patients receiving home therapy or no therapy (17.1 vs. 20.3 days).

Table 1.

Demographics of our Sample Population. Home Therapy Versus No Therapy.

Therapy type	Mean age (P < .34)	Male	Right hand dominant	Dominant hand surgery
Home therapy (n = 50)	56 ± 14.8	15 (30%)	40 (80%)	34 (68%)
No therapy (n = 55)	59 ± 13.4	19 (34.5%)	48 (87.3%)	42 (76%)

In the home therapy group undergoing surgery, all 42 patients had baseline QuickDASH, BCTQ FSS, and BCTQ SSS scores. Thirty-four patients provided these scores at 2 weeks after surgery, 18 at 6 weeks, and 21 at 3 months postsurgery. Among patients receiving no therapy, 48 provided baseline scores. Forty-two provided scores at 2 weeks postoperatively, 27 at 6 weeks, and 33 at 3 months. Quick Disabilities of the Arm, Shoulder, and Hand, BCTQ FSS, and BCTQ SSS scores all significantly improved over time for those receiving home therapy as well as those receiving no therapy, and there was no significant difference in the magnitude of improvement among QuickDASH, BCTQ FSS, and BCTQ SSS scores between both groups from baseline to 3 months postoperatively. Student’s T-tests confirmed no significant difference between mean QuickDASH, BCTQ FSS, or BCTQ SSS scores at preoperative levels or any postoperative visit between both groups (Tables 2-4). An intention-to-treat analysis was conducted which confirmed significant improvement of QuickDASH, BCTQ FSS, and BCTQ SSS scores over time (P value < .05) as well as no significant difference in the magnitude of improvement between patient’s receiving home therapy and those receiving no therapy.

Table 2.

As-Treated Analysis of QuickDASH Score of No Therapy vs Home Therapy.

As-treated outcome variables	No therapy	Home therapy	P value for comparison of means (Student’s T-test)
QuickDASH Pre op	48.30 ± 20.74 (n = 48)	50.87 ± 20.96 (n = 42)	.57
QuickDASH 2 wk	40.02 ± 22.62 (n = 41)	36.36 ± 15.82 (n = 34)	.43
QuickDASH 6 wk	23.91 ± 16.83 (n = 25)	28.16 ± 23.21 (n = 18)	.49
QuickDASH 12 wk	16.46 ± 16.87 (n = 29)	21.53 ± 20.08 (n = 19)	.35
P value for time across both groups (1-way repeated measures of ANOVA)	<.05
P value for group*time interaction (Mixed ANOVA)	.58

Note. ANOVA = analysis of variance; QuickDASH = Quick Disabilities of the Arm, Shoulder, and Hand. Values shown are the mean.

Table 3.

As-Treated Analysis of BCTQ FSS No Therapy vs Home Therapy.

As-treated outcome variables	No therapy	Home therapy	P value for comparison of means (Student’s T-test)
BCTQ FSS Pre op	2.67 ± 0.88 (n = 48)	2.85 ± 0.90 (n = 42)	.34
BCTQ FSS 2 wk	2.38 ± 0.97 (n = 42)	2.43 ± 0.77 (n = 34)	.80
BCTQ FSS 6 wk	1.95 ± 0.78 (n = 27)	1.97 ± 0.76 (n = 18)	.96
BCTQ FSS 12 wk	1.63 ± 0.72 (n = 33)	1.77 ± 0.76 (n = 21)	.47
P value for time across both groups (1 way repeated measures of ANOVA)	<.05
P value for group*time interaction (Mixed ANOVA)	.10

Note. BCTQ = Boston Carpal Tunnel Questionnaire; FSS = functional status scale; ANOVA = analysis of variance. Values shown are the mean.

Table 4.

As-Treated Analysis of BCTQ SSS No Therapy vs Home Therapy.

As-treated outcome variables	No therapy	Home therapy	P value for comparison of means (Student’s T-test)
BCTQ SSS Pre op	3.33 ± 0.82 (n = 48)	3.28 ± 0.86 (n = 42)	0.78
BCTQ SSS 2 wk	2.05 ± 0.81 (n = 42)	1.80 ± 0.59 (n = 34)	0.14
BCTQ SSS 6 wk	1.63 ± 0.61 (n = 27)	1.84 ± 0.67 (n = 18)	0.29
BCTQ SSS 12 wk	1.50 ± 0.68 (n = 33)	1.49 ± 0.51 (n = 21)	0.97
P value for time across both groups (1 way repeated measures of ANOVA)	< 0.05
P value for group*time interaction (Mixed ANOVA)	0.30

Note. BCTQ = Boston Carpal Tunnel Questionnaire; SSS = symptom severity scale; ANOVA = analysis of variance. Values shown are the mean.

Among patients receiving surgery, the mean NRS pain scores significantly improved regardless of postoperative therapy protocol (home therapy P-value < .05; no therapy P-value < .05), and there was no significant difference in magnitude of improvement between treatment groups (P = .40). For patient’s receiving no therapy, the mean NRS pain score improved from a baseline of 4.5 to 1.5 at 3 months postoperatively. Patients receiving home therapy improved from a baseline mean of 4.7 to 2.0 at 3 months after surgery (Table 5). An intention-to-treat analysis also revealed significant improvement in NRS scores in both groups (P < .05 for both home therapy and no therapy) without a significant difference in magnitude of improvement (P = .46). Grip strength improved significantly over time in both groups (home therapy P < .05; no therapy P < .05), and there was no significant difference in magnitude of improvement (P = .85). Intention-to-treat analysis showed similar findings (P < .05, P = .40). There was no significant improvement in hand circumference over time in either the home therapy or no therapy patient groups in both as-treated and intention-to-treat analyses. Finally, patients demonstrated no significant difference in key pinch, chuck pinch, or static 2-point discrimination between the therapy and no therapy group in either the as-treated or intention-to-treat analysis.

Table 5.

As-Treated Variable Outcomes.

As-treated
Outcome variables	Therapy			No therapy
	Mean	SD	N	Mean	SD	N
NRS pain (pre op)	4.7	3.40	50	4.5	3.54	55
NRS pain (2 wk)	2.6	2.65	34	2.3	2.62	40
NRS pain (6 wk)	3.4	2.79	18	2.0	2.42	27
NRS pain (12 wk)	2.0	2.04	21	1.5	1.87	33
Grip strength pre op, kg	37	18.7	50	35	17.8	55
Grip strength (2 wk), kg	18	12.6	32	18	14.6	33
Grip strength (6 wk), kg	28	16.9	14	32	17.9	20
Grip strength (12 wk), kg	28	14.9	8	36	19.7	12
Chuck pinch strength (pre op), kg	5	2.1	50	4	2.1	55
Chuck pinch strength (2 wk), kg	4	1.7	32	4	2.1	33
Chuck pinch strength (6 wk), kg	4	2.4	14	5	2.3	20
Chuck pinch strength (12 wk), kg	4	2.4	8	5	2.1	12
Key pinch strength (pre op), kg	6	2.3	50	6	2.4	55
Key pinch strength (2 wk), kg	5	2.3	32	5	2.0	33
Key pinch strength (6 wk), kg	6	2.5	14	6	2.1	20
Key pinch strength (12 wk), kg	5	2.4	8	6	2.5	12
Hand circumference (pre op), mm	206	16.9	50	208	18.2	55
Hand circumference (2 wk), mm	203	16.5	32	206	22.2	33
Hand circumference (6 wk), mm	201	11.8	14	209	18.5	20
Hand circumference (12 wk), mm	203	13.8	8	199	14.3	12
2PD small finger (pre op), mm	6	1.8	50	6	2.4	55
2PD small finger (2 wk), mm	6	2.0	32	5	0.6	33
2PD small finger (6 wk), mm	5	0.6	14	5	0.4	20
2PD small finger (12 wk), mm	5	0.4	8	5	0.4	12
2PD index finger (pre op), mm	6	2.2	50	6	2.8	55
2PD index finger (2 wk), mm	6	2.4	32	5	0.9	33
2PD index finger (6 wk), mm	5	0.8	14	5	0.3	20
2PD index finger (12 wk), mm	5	0.4	8	5	0.3	12
2PD thumb (pre op), mm	7	2.8	50	7	3.0	55
2PD thumb (2 wk), mm	6	2.4	32	6	2.3	33
2PD thumb (6 wk), mm	6	1.4	14	5	0.9	20
2PD thumb (12 wk), mm	5	0.4	8	5	0.00	12

Note. NRS = numerical pain rating scale; 2PD = 2-point discrimination.

Discussion

Carpal tunnel syndrome is commonly treated surgically,^15,16 but the optimal postoperative protocol is debated. The most recent AAOS CPG identify no high-quality evidence comparing home therapy to no therapy following surgery.^1,15 This study’s purpose is to compare the outcomes of patients receiving instructions for a formal home therapy regimen and patients receiving no formal hand therapy following endoscopic CTR. The no formal therapy group were instructed to perform activities and range of motion to their tolerance while being restricted to a 5-pound weight limit until the sutures were removed.

Our results showed that QuickDASH, BCTQ FSS, and BCTQ SSS showed statistically significant improvement in both treatment groups between patients randomized to receive no formal therapy and patients receiving instructions for a home therapy regimen, but the improvement in all 3 outcome scores did not significantly differ between treatment groups. The improvement in other measures, including NRS, pinch strength, and hand circumference, also did not significantly differ between treatment groups over time. Therefore, we accept our hypothesis as these results indicate home therapy exercises following CTR may not significantly benefit patients when compared to no therapy.

Previous studies have investigated optimizing post CTR outcomes with a variety of postoperative treatments and rehabilitation protocols.^{17 -24} Provinciali et al randomized patients undergoing open CTR to either a multimodal supervised rehabilitative treatment program or a progressive home exercise program. Outcomes included BCTQ and return to work as well as measures of hand dexterity including the Jepsen-Taylor test and 9-hole peg test. While this study showed no difference in BCTQ scores between groups postoperatively and no difference in motor performance at 3 months after surgery, the patients receiving detailed home therapy exercises did return to work approximately 10 days sooner. Therefore, the authors concluded a premade hand regimen accelerated the recovery of patients undergoing CTR but did not correlate with long-term functional benefit. ²⁴ As delivery of cost-conscious medical care becomes increasingly important, other studies have explored postoperative physical therapy following CTR from a cost perspective. Pomerance and Fein conducted a study randomizing patients to receive home therapy exercises or home therapy exercises in addition to a 2-week therapist-directed rehabilitative program. DASH scores, return to work, grip and pinch strength, and pain scores did not significantly differ between groups. The authors argue against supervised physical therapy given the added cost with no measurable difference in patient outcomes. ¹² Similar to our study, this study indicated that formal physical therapy did not influence clinical outcomes as evidenced by similar BCTQ or DASH scores between groups; however, these authors did not investigate the role of no therapy in the postoperative setting.

Recently, Gil et al performed a study comparing patients undergoing mini-open CTR receiving 3 different postoperative protocols. These included no formal therapy, accelerated therapy consisting of 1 visit with a hand therapist, or 6 weeks of formal hand therapy. Again, this study showed no difference among patients’ QuickDASH scores regardless of postoperative rehabilitation plan and they concluded formal hand therapy was unnecessary follow CTR. ¹¹ These results are consistent with our study’s findings of uniform improvement in patient questionnaire outcomes with and without postoperative hand therapy. However, these authors acknowledge QuickDASH scores are not specific to CTR and suggested that disease-specific questionnaires may more appropriately detect differences in this patient population. Our study attempts to account for this by also utilizing BCTQ in an attempt to be more disease specific.

All patients enrolled in our study received an endoscopic CTR. To our knowledge, all other studies examining the role of hand therapy following CTR has examined an open or mini-open surgical technique patient population. As endoscopic surgery increases in popularity, ⁵ this patient population remains under reported. Particularly, as recent evidence has suggested quicker return to work following endoscopic CTR when compared to open techniques, ⁶ it has remained unclear what role postoperative therapy may play in this setting. Our study attempts to fill this void in the literature, but we do acknowledge our conclusions may or may not apply to open and mini open procedures. Surgeons utilize different validated questionnaires to assess postoperative outcomes in the CTR patient population.^{18 -21} In addition to the widely used QuickDASH questionnaire, we employed the BCTQ in an attempt to be more disease specific for the CTR population.

Our study has limitations that must be discussed, starting with the lack of complete follow-up among our patients as a weakness of our study. Our analysis attempted to account for follow-up by utilizing an intention-to-treat statistical model to confirm our as-treated analysis. Multiple attempts to contact patients via telephone often went unreturned. Furthermore, many patients with considerable improvement following surgery fail to follow-up after their first postoperative visit. This behavior makes data collection difficult, but it is consistent with real-world clinical situations. This could theoretically worsen recorded outcomes as patients with better outcomes may disproportionately be lost to follow-up. Worker’s compensation cases were not included in this study, possibly making these results less generalizable. Furthermore, within the home therapy group, we did not aim to elucidate what type of therapy these patients did, if any, and how often they did it. However, the authors believe that this lack of discrete instructions or a need for follow-up is all part of the success of a nonsupervised home therapy program. We also did not measure how conforming patients in the formal therapy cohort were to their prescribed therapy regimen which could have affected the postoperative improvements measured in this group. We also did not attempt to directly analyze stiffness through range of motion testing. We believe stiffness could be related to other unrelated pathologies such as arthritis or tendonitis that could confound outcomes. Our study did not attempt to stratify patients based on severity of preoperative symptoms. These could be areas of future research to further stratify patients in order to identify if subsets of patients would receive greater benefit from formal hand therapy.

Conclusions

This blinded, prospective randomized controlled study shows no significant difference in improvement of QuickDASH, BCTQ SSS, and BCTQ FSS scores between patients receiving no therapy and home therapy following endoscopic CTRS. Consideration should be given to releasing patients without supervised therapy in the postoperative setting.