Key-words:
Carpal tunnel syndrome - mini-incision - outcome
Introduction
Carpal tunnel syndrome (CTS) is the most frequently encountered entrapment neuropathy.[[1]] The etiology of CTS is largely structural, genetic, and biological, with environmental
and occupational factors.[[2]] The main symptom of CTS is intermittent numbness of the thumb, index, long fingers,
and radial half of the ring finger.[[3]] Because of CTS is one of the most frequent conditions that lead to work disability;
therefore, many numbers of conservative and surgical treatments have been performed.
Patients who had severe, advanced CTS who are unresponsive to conservative management
candidate faced to open surgeries with different approach. After comparing all techniques,
there are some advantages and disadvantages for all.[[4]],[[5]] The important goals for patients on each surgery treatment are relief of symptoms,
earlier rehabilitation, cosmetic satisfaction, and cost-effectiveness of procedure.
Many of those approaches on carpal tunnel release reach the patients to these goals.[[6]],[[7]] For this purpose, our study performed carpal tunnel decompression using 1.5 cm
longitudinal mini-incision procedure. The outcomes obtained to introduce the advantages
and disadvantages of this technique. Various limited skin incisions and endoscopic
techniques have been proposed as a minimally invasive and effective for preventing
of the excessive scar formation and the achieving of a better cosmetic results.[[8]] Physical therapy following surgery has been done which is very helpful to restore
wrist strength.
Methods
For this prospective, randomized clinical study, carpal tunnel release was performed
on 300 hands (188 patients), between March 2011 and 2015. Each patient was diagnosed
to be having carpal tunnel compression neuropathy based on clinical symptoms, signs,
and nerve conduction studies. Initially, conservative treatment, including rest, bracing,
and nonsteroidal anti-inflammatory medications, was administered. Patients who diagnosing
for CTS within 3 years, being in good general health, having very slow nerve conduction
results but good muscle strength, and finally having symptoms that are worse at night
than during the day included in this study. Those patients who having very severe
symptoms such as continual numbness, muscle weakness and wasting, and very poor nerve
conduction results with other upper extremity problems and chronic underlying medical
condition were excluded from this study. Because all patients faced to full criterion
for surgical neurolysis, the ethical approval was not required in accordance with
the policy of our institution. Patients were received surgical treatment using 1.5
cm longitudinal mini-incision procedure. A total of 300 hands for 188 patients with
severe, advanced CTS underwent carpal tunnel release through a 1.5 cm longitudinal
mini-incision between March 2011 and 2015. There were 132 (70%) females and 56 (30%)
males with a mean age of 40 ± 29.5 years (ranging from 24 to 73) and female to male:
2.36. A total of 178 operations were performed for the right hand and 122 for the
left hand. The operations were done in two experimental university hospitals (Emam
Reza Hospital and Taleghani Hospital). Before surgery, all patients were evaluated
for physical examination and electromyelography (EMG). Persistent night pain and numbness
associated with EMG study which showed moderate and severe CTS in all patients. The
pain status of the patients was pre- and post-operatively assessed with the Global
Symptom Score (GSS).[[9]] Clinical results and patients' satisfaction were evaluated with the Visual Analog
Patient Satisfaction Scale (VAPSS) postoperatively.[[10]],[[11]]
Surgery procedure
Before surgery, the affected hand, wrist, and forearm were cleaned with povidone-iodine
solution. The area to be operated was covered with a sterile compress. Pneumatic tourniquet
was used. An ideal hand position is obtained with a wrist extension of 30 degrees,
the handheld in place by a cushion placed under the wrist joint and with the thumb
abducted. Local anesthesia, using 2% xylocain 5 cc and isotonic SF 5 cc as performed.
In our study, the mini-open carpal tunnel release is a relatively new technique that
consists of a longitudinal incision that varies from 1.5 cm placed in the radial border
of the ring finger line which is beginning about 2 cm to the distal flexure wrist
crease [[Figure 1]]a. The incised skin was retracted with the help of a miniretractor and subcutaneous
fat tissue was dissected laterally. A small opening done in the carpal ligament with
a fine scissors or surgical blade and a dissector was introduced beneath the carpal
ligament, and then, the ligament was cut with surgical blade. After the homeostasis,
the skin was sutured with 4/0 sutures mattress [[Figure 1]].
Figure 1: It showed a longitudinal incision that varies from 1.5 cm placed in the radial border
of the ring finger line which is beginning about 2 cm to the distal flexure wrist
crease (flexor carpi radialis, flexor carpi ulnaris, kaplan cardinal line, radial
side ring finger line, red line is incisional site) (a) The incised skin was retracted
with the help of a miniretractor and subcutaneous fat tissue was dissected laterally
(b) The ligament was cut with surgical blade (c) The skin was sutured with 4/0 sutures
mattress
A postoperative elastic bandage was applied to all patients, allowing early active
motion. The stitches were removed after 7 days. Patients underwent physical therapy
after surgery to restore wrist strength. The mean of operation duration time was 12
± 3.5 min (ranging between 8 and 15 min). The mean hospital stay was 2.5 h (ranging
between 3 and 5 h). All patients were evaluated the clinical effects using the GSS
that in which points are given on a 1–10 scale for pain, numbness, paresthesias, weakness,
and nocturnal awakening, and a Visual Analog Patient Satisfaction Scale described
by Kilincer and Zileli evaluated the patients for cosmetic results (0–3), return to
daily activities (0–3), palmar tenderness (0–3), and scar sensitivity (0–3).[[6]],[[10]],[[11]]
Results
In this group, 300 carpal tunnel release operations were done on 188 patients using
1.5 cm longitudinal mini-incision. During surgery procedure, there is no evidence
of local hematoma or nerve injury. There are no procedure-related complications such
as skin infection, tenderness of scar, excessive scar formation, and stiffness during
the follow-up period. All symptoms have been relieved immediately after surgery and
full recovery after surgery took average 2 months for all patients. The mean preoperative
GSS score was 7 ± 2.5 which decreased to 1.3 ± 0.34 postoperatively (P < 0.002). Postoperatively,
the mean VAPSS score has been improved to 8.3 ± 1.5 during the follow-up period. In
this study, six hands complained of residual mild pain with tenderness of scar and
three hands had temporary median nerve neuropraxy which improved 2 weeks after surgery
and muscle force of abductor pollicis brevis reinforced. We did not have incomplete
release of the ligament and extensive scarring in site of incision [[Table 1]]. Therefore, there are no reasons for procedure failure. In our study, no patient
required repeat operations. Five patients (seven hands) loosed strength of their wrist
because the carpal ligament was cut completely. These patients underwent physical
therapy after surgery and restore their wrist strength after 1 month. There is no
patient underwent reoperation because there is no recurrence of symptoms. The mean
time recovery appeared to be fast and generally stay out of work for at least 2 weeks
return to daily activities and all patients recover completely.
Table 1: Pre- and post-operation scores of pain, numbness, paresthesias, weakness and nocturnal
awakening, cosmetic results, return to daily activities, palmar tenderness, and scar
sensitivity of the patients operated with 1.5 cm longitudinal mini-incision in 300
hands based on Global Symptom Score and visual analog patient satisfaction scale
Discussion
The CTS is the most common compressive neuropathy in clinical practice. It is caused
by the compression of the median nerve at the wrist, more precisely at the carpal
tunnel. It effects mainly middle-aged population and mostly females.[[12]],[[13]],[[14]],[[15]],[[16]] In our study, CTS was more frequent in women (female/male: 1.47) and in the right
hand with a mean age of 40 ± 29.5 years. The general clinical presentation is of painful
paresthesias and/or burning pain in the lateral half of the hand, predominantly in
the three first fingers. Typically, the paresthesias are predominantly nocturnal.
The patients may also complain of anesthesia, loss of dexterity, weakness, and in
more advanced cases loss of motor function and thenar atrophy.[[17]],[[18]] Surgical treatment of CTS consists of the division of the transverse carpal ligament
which reduces the pressure on the median nerve by increasing the space in the carpal
tunnel.[[14]] Many surgical techniques have been used to treat CTS such as the classical open
carpal tunnel release technique, the “mini-open” or limited visualization techniques,
and the endoscopic carpal tunnel release methods. Other studies reported that endoscopic
release results in less pain in the early postoperative period and a quicker return
to work and less wound complications but showed a higher risk of median nerve injury.[[19]],[[20]],[[21]] Mini-incision release is a less invasive technique, lower rate of complications,
shorter operative time, and more cost-effective. Although each technique has advantages
and disadvantages. A few studies reported that the mini-incision release technique
decreases the pathologic swelling of the median nerve and scar formation at the inlet
of the carpal tunnel.[[22]],[[23]] Likewise, several publications on endoscopic release have also reported possibly
higher cost and higher risk of nerve injury.[[24]] The advantages and disadvantages of the above techniques are a matter of debate,
but their common goal is to release the median nerve by completely transecting the
flexor retinaculum.
In previous studies, some authors have worked on multiple limited mini-open incision
approaches on CTS management to decrease the postoperative morbidity.[[25]],[[26]],[[27]],[[28]],[[29]] Mini-open procedures have been introduced in some patterns such as a longitudinal
wrist incision, minitransverse wrist incision, midpalmar accurate incision, palmar
incision, and double-incision technique. However, those techniques are safe and effective
as reported by authors, but it has some complications.[[30]] Those surgical techniques are performed under direct vision, early complications
including incomplete release of carpal ligament, artery and nerve injuries, and local
hematoma are rare in mini-open median nerve release.[[30]] Furthermore, hypertrophic scar formation, scar tenderness, pillar pain, loss of
grip strength, and sympathetic dystrophy led to delay of returning to daily activities
or work and emotional distress in different open surgeries [[31]] In this study, we aimed to analyze the outcome of patients operated for CTS using
1.5 cm longitudinal approach. We reported that the early and late complications including
pain, palmer tenderness, scar sensitivity, stiffness, and limited strengthened and
cosmetic problems became less. In this study, the mean VAPSS score was 1.8 when the
patients were evaluated for cosmetic results, return to daily routine activities,
palmer tenderness, and scar sensitivity. A study from Iraq worked on 228 hands with
CTS using 1.5 cm palmer skin incision technique for carpal tunnel release. Their results
showed better VAPSS score and less complications than other standard techniques and
the mean VAPSS score was 8.7 postoperatively.[[32]] In our group, all patients have complete remission of symptoms which is near the
results of the literatures those used mini-open incision approaches.[[16]],[[33]],[[34]] However, we did not experience any artery, nerve, or tendon injury during using
1.5 cm longitudinal mini-incision technique which was seen in some previous studies
using mini-open surgeries.[[15]] Other study performed to total 93 wrists of 79 patients with CTS and compare minilongitudinal
and transverse incision approaches. They reported that longitudinal incision is more
effective to relief symptoms and better functional outcomes than transverse incision
and there was less scar formation with transverse incision.[[35]] Other study operated 143 carpal tunnel releasing procedures using a limited uniskin
incision. There was no complication such as bleeding or nerve injury in the operated
patients during average 13-month follow-up period. The mean visual analog scale score
was 7.9 preoperatively and 2.8 postoperatively and the mean VAPSS score was 8.1. These
results are really similar to our results.[[16]]
Conclusion
1.5 cm longitudinal mini-incision is a valuable and bearable procedure because it
is minimally invasive with shorter operative time. The early and late complications
including bleeding, pain, palmer tenderness, scar sensitivity, stiffness, and limited
strengthened and cosmetic problems became less. Furthermore, return to daily routine
activities was shorter with good patient satisfaction and low need recurrent therapy
and rehabilitation costs. However, this approach requires more experience for surgeon
to do the best.
