Effectiveness of an Endoscopic Recurrent Branch Release Procedure Combined with Standard Endoscopic Carpal Tunnel Release Surgery Compared to Standard Endoscopic Carpal Tunnel Release Surgery Alone: A Propensity Score-Matched Study.

Background: The purpose of this study is to compare the effectiveness of endoscopic release of the recurrent branch from surrounding soft tissue in combination with standard endoscopic carpal tunnel release (ECTR) surgery to standard ECTR surgery alone in patients with established abductor pollicis brevis (APB) muscle weakness. Methods: Using propensity score matching, we compared the recovery rates of postoperative clinical symptoms in patients with idiopathic carpal tunnel syndrome in whom the preoperative Medical Research Council (MRC) scale of the APB muscle (MRC-APB) was zero (no contraction) and with undetectable distal motor latency (DML) of APB, to those who underwent standard ECTR surgery alone and those who underwent recurrent branch release in addition to standard ECTR. Results: Forty-nine hands in the recurrent branch release group and 49 hands in the standard ECTR surgery group were extracted. There were statistically significant differences in postoperative recovery rate from MRC-APB 0 to '4 or 5' at 30 months (OR: 2.42; 95% CI: 1.03-5.67; p = 0.04) and at final follow-up (OR: 2.64; 95% CI: 1.11-6.26; p = 0.03). There were statistically significant differences in postoperative recovery of MRC-APB scales at 24 months (p = 0.03), 30 months (p = 0.02) and at final follow-up (p = 0.02). There were statistically significant differences in postoperative recovery of DML (p = 0.04). Conclusions: Endoscopic release of the recurrent branch in combination with standard ECTR surgery showed better recovery rates in MRC-APB and DML recovery compared to standard ECTR surgery alone. Level of Evidence: Level III (Therapeutic).

A Minimally Invasive Full Endoscopic Approach to Tibial Nerve Neurolysis in Diabetic Foot Neuropathy: An Alternative to Open Procedures.

BACKGROUND: Dellon et al. have reported that chronic nerve compression of the tibial nerve inside the tarsal tunnel, caused by diabetes mellitus, can be relieved following open decompression surgery. However, the large skin incision resulting from Dellon's procedure may cause wound healing problems. The authors report the possibility of a minimally invasive full endoscopic procedure. METHODS: Operations were performed under local anesthesia without a pneumatic tourniquet. An anesthetic agent was applied at the proximal part of the flexor retinaculum of the foot, and a hypodermic needle was advanced into the tarsal tunnel. Tarsal tunnel pressure and blood circulation of the tibial nerve using indocyanine green assessment were measured preoperatively. One 1-cm portal skin incision was made at the anesthetized area and the Universal Subcutaneous Endoscope system was inserted into the tarsal tunnel. The flexor retinaculum, tibial nerve, blood vessels, and abductor hallucis muscle fascia were identified under endoscopic observation. After decompression of the tarsal tunnel, the authors measured tarsal tunnel pressure and blood circulation of the tibial nerve for analysis of the effectiveness of the endoscopic decompression during the procedure. RESULTS: Fourteen operations were compiled and analyzed. Postoperative clinical status was improved based on the preoperative modified Toronto Clinical Neuropathy Score. The mean tarsal tunnel pressure dropped to 4.5 mmHg during surgery from the initial preoperative 49.4 mmHg in resting position. Endoscopic indocyanine green assessment showed more than 30 percent improvement of the vascularity surrounding the tibial nerve. CONCLUSION: The authors' minimally invasive full endoscopic procedure is a viable alternative approach for tarsal tunnel syndrome patients with diabetic foot neuropathy. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

A Median Nerve Anterior Transposition Procedure for Multi-Recurrent Hemodialysis-Related Carpal Tunnel Syndrome.

BACKGROUND: Some long-term hemodialysis patients suffer from multi-recurrent carpal tunnel syndrome because amyloid originating from ß2-microglobulin continues to be deposited mainly in the flexor tendons, tendon sheaths and flexor retinaculum during maintenance hemodialysis. These amyloid deposits inside carpal canal (tunnel) tissues increase carpal canal pressure and this leads to compression of the median nerve. When multi-recurrent carpal tunnel syndrome occurs, previous operative scarring of soft tissue may prohibit further enlargement of the carpal canal even if any carpal canal decompression procedure is used. For this reason, we developed a median nerve anterior transposition procedure, as a new approach in the treatment of multi-recurrent hemodialysis-related carpal tunnel syndrome. METHODS: Median nerve anterior transposition procedures were performed on seven hands in six patients with multi-recurrent carpal tunnel syndrome. The mean age of the patients was 68.3 years and the mean hemodialysis duration was 35.3 years. Mean follow-up period was 9.9 months. The median nerve is transposed from inside to outside of the carpal canal under local and infiltration anesthesia without a pneumatic tourniquet on an outpatient basis. This procedure is based on the same principles applied in ulnar nerve anterior transposition procedures for cubital tunnel syndrome. RESULTS: Main preoperative patient complaints were intolerable tingling and/or pain in the diseased hands throughout the day. Following the surgeries, preoperative clinical symptoms began to subside and eventually improved in all hands. Postoperative abductor pollicis brevis muscle power using manual muscle testing improved except in one hand. Abnormal preoperative distal motor and sensory latency were improved except in two hands following the surgeries. CONCLUSIONS: The median nerve anterior transposition procedure is a beneficial treatment for patients suffering from hemodialysis-related multi-recurrent carpal tunnel syndrome.

Endoscopic tarsal tunnel syndrome surgery using the Universal Subcutaneous Endoscope system.

BACKGROUND/OBJECTIVE: Tarsal tunnel syndrome is a relatively rare entrapment neuropathy with the lateral and medial plantar nerves entrapped inside of the tarsal tunnel. When conservative treatment fails, standard open decompression of the nerve can be achieved by releasing the flexor retinaculum of the foot through a several-centimetre-long skin incision made along the tarsal tunnel. By contrast, we made a 1-cm portal incision at the proximal part of the medial ankle, and endoscopic tarsal tunnel release of the flexor retinaculum of the foot and part of the abductor hallucis muscle was achieved using the Universal Subcutaneous Endoscope (USE) system. METHODS: Our procedure was performed under local anaesthesia without a pneumatic tourniquet on an outpatient basis. The USE system was inserted into the tarsal tunnel at the proximal part of the medial ankle; the nerves, vessels, flexor retinaculum, tendons of the foot, and the abductor hallucis muscle were then endoscopically identified. Decompression of the lateral and medial plantar nerves entrapped inside of the tarsal tunnel was then achieved by releasing the flexor retinaculum of the foot and part of the abductor hallucis muscle with a push knife under complete endoscopic observation. RESULTS: Results from eight feet of five patients were compiled and analyzed. All showed improved clinical signs compared with their preoperative condition. CONCLUSION: Our less invasive endoscopic management for tarsal tunnel syndrome using the USE system produces sufficient results.

Retrospective analysis of five-year and longer clinical and electrophysiological results of the world's first endoscopic management for carpal tunnel syndrome.

We have analyzed postoperative long-term follow-up results of five years or more from idiopathic carpal tunnel syndrome patients that underwent our complete carpal canal release and decompression procedure that uses the Universal Subcutaneous Endoscope system. In this series, 203 hands were followed up both clinically and electrophysiologically. Final follow-up times were determined by the most recent electrophysiological measurements. Mean follow-up period was nine years. Tingling, pain (using a 3 gm needle) and touch (using a 2 gm von Frey hair) at all median nerve distribution areas recovered to normal in 92.9, 98.2, 95.2%, respectively. Abductor pollicis brevis muscle power improved from preoperative manual muscle testing of 0, 1, 2 to post-operative 4 or 5 in 82.6%. Mean detectable distal sensory latency improved from 4.3 (n = 130) to 3.1 msec (n = 200). Mean detectable distal motor latency improved from 6.2 (n = 189) to 4.1 msec (n = 200). Complication and recurrence rates were 0% and 0.5% respectively.

Comparison of clinical results between elderly and younger patients following endoscopic carpal tunnel release surgery for idiopathic carpal tunnel syndrome.

We retrospectively analyzed clinical results of 107 hands of an elderly idiopathic carpal tunnel syndrome group (65 years old and older) and 234 hands of a younger group (under 65 years old) following endoscopic carpal canal release surgery. There were statistical differences in recovery rates for tingling, pain sensation and touch sensation (p < 0.01) and recovery periods of touch sensation (p < 0.05). There were no statistical differences in recovery rates, periods of thumb abduction muscle power, and recovery rates of electrophysiological examination results. Cervical spondylosis may affect postoperative recovery of subjective sensory disturbance, especially in the elderly group. From these results, in elderly patients we recommend primary minimally invasive endoscopic carpal canal release surgery and only apply primary opponoplasty in cases when the patient strongly wishes reconstruction faster than six months.

Opponoplasty without postoperative immobilization.

Opponoplasty using tendon transfer is a useful reconstructive procedure that restores lost thenar muscle function. Tendon transfers, however, require postoperative immobilization periods of up to four weeks before the sutured tendons reach required strength. We developed an opponoplasty procedure using α-TCP (alpha-tricalcium phosphate) cement that does not require postoperative immobilization and was applied to nine hands out of nine cases. The procedure is performed under local anesthesia without a pneumatic tourniquet and on an outpatient basis. In this procedure, the flexor digitorum superficialis of the ring finger is used as the donor tendon and the palmaris longus tendon is used as a dynamic pulley. The distal end of the transferred tendon is anchored to the inside of a newly formed bone hole in the thumb's proximal phalanx using α-TCP cement. Our opponoplasty procedure was uneventful postoperatively and produced satisfactory results in all nine cases. The α-TCP cement procedure shows potential for other tendon transfer applications.

How I developed the world's first evidence-based endoscopic management of carpal tunnel syndrome.

Carpal tunnel syndrome has been surgically treated by release of the transverse carpal ligament (flexor retinaculum of the hand) using a blind procedure since 1930 or by an open procedure since 1946. The blind procedure has the possibility of unreliable results and ensuing complications, hence, the open procedure was developed. The open procedure, however, also resulted in various complications as reported in the 1970s. At the end of the 1970s, I had many questions regarding accepted surgical procedures for treatment of carpal tunnel syndrome. These included: "Why should any healthy tissue be injured?"; "How can I make operations as minimally invasive as possible?"; and "How can I shorten postoperative fixation periods that cause declines in activities of daily living?" This paper describes how I developed the world's first evidence-based endoscopic management procedure for carpal tunnel syndrome using local anaesthesia without a pneumatic tourniquet on an outpatient basis.

Characteristics of dialysis-related amyloidosis in patients on haemodialysis therapy for more than 30 years.

BACKGROUND: Dialysis-related amyloidosis is one of the chronic the complications of haemodialysis. We conducted an investigation of dialysis-associated amyloidosis in extremely long-term survivors. METHODS: Twenty-one patients on haemodialysis for more than 30 years ('30+' group) and 13 patients on haemodialysis for 20-30 years ('20-30' group) at Sangenjaya Hospital were enrolled in this study. The frequencies of operations for conditions related to haemodialysis-related amyloidosis were examined. RESULTS: The mean age at the start of haemodialysis was younger in the '30+' group (29.1 +/- 7.3 years) than in the '20-30' group (40.5 +/- 8.2 years, P = 0.0003). Eighteen (85.7%) patients had undergone surgery for CTS, six (28.6%) had undergone surgery for trigger finger and six (28.6%) had undergone surgery for cervical destructive spondyloarthropathy (DSA) at 30 years after the start of haemodialysis therapy. Patients who were over the age of 30 years at the start of dialysis therapy more frequently underwent CTS operations (100%) than those who were under 30 years of age at the start of dialysis (76.9%; P = 0.025) in the '30+' group at 30 years after the start of haemodialysis. The frequencies of operations for CTS did not differ significantly between the '20-30' group and the '30+' group. CONCLUSIONS: Haemodialysis-associated amyloidosis was common in extremely long-term survivors. Even though the mean age at the start of haemodialysis was younger in the '30+' group than in the '20-30' group, the frequency of operations for CTS did not differ. This may be attributable to the recent advances in haemodialysis technologies.

[Operative treatment for carpal tunnel syndrome].

Carpal tunnel syndrome is an entrapment neuropathy where the median nerve is compressed inside of the carpal canal. Causes of this syndrome include repetitive strain, wrist fracture, rheumatoid arthritis, space-occupying lesion, dialysis-related amyloidosis, diabetes mellitus, and in addition, cases with no apparent cause. Similar symptoms such as numbness, sensory disturbance of the median nerve distribution area and weakness of thenar muscles also occur in patients who suffer from cervical diseases. In cases where the patient suffers from both carpal tunnel syndrome and cervical disease, the patient's complaints may not disappear if treatment is only performed for one of them. Therefore, accurate diagnosis of the cause of the symptoms, using electrophysiological test results and/or carpal canal pressure measurement results is essential to the successful treatment of such patients. The purpose of operative treatments for carpal tunnel syndrome is to decompress the median nerve. A variety of operative treatment techniques, i.e., standard open procedure, minimum incision open procedure, one-portal or two-portal endoscopic procedures, etc., are used. Every procedure has different conditions such as equipment used, operative hand positions, location and size of skin incisions, blind ways or no blind ways, approaches to target tissues, tourniquet usage and others. I developed the world's first endoscopic operative procedure for carpal tunnel syndrome using the Universal Subcutaneous Endoscope (USE) system in 1986 and I have operated on over 7,300 hands during these last 20 years. My technique has been proven by pre- and postoperative carpal canal pressure and intraneural median nerve pressure measurement results as an evidence-based medicine. Before an operative method is chosen, the most important thing to consider is whether or not it will safely and completely achieve the purpose as evidence-based medicine with minimal invasion of the patient.

Results of endoscopic management of primary versus recurrent carpal tunnel syndrome in long-term haemodialysis patients.

In long-term haemodialysis patients, carpal tunnel syndrome (CTS) frequently occurs as a result of amyloid deposition, originating from beta-2 microglobulin, to the flexor retinaculum, paratenons and tendons themselves, which leads to an increase in carpal canal pressure and compression of the median nerve. Surgical procedures can rectify the condition, but continuing maintenance haemodialysis sometimes causes recurrence. We endoscopically operated 1848 hands primarily, 104 recurrent post-endoscopic procedure hands and 130 recurrent post-open procedure hands using the Universal Subcutaneous Endoscope (USE) system, then analysed clinical symptoms and electrophysiological recovery for more than six months post-operatively. The patients were satisfied with the clinical results. Optimal electrophysiological improvements were reported. There were no statistical differences between three groups, except in recovery of touch sensation, which was better in the post-endoscopic group than in the post-open group. There were no complications in this series. Our minimally invasive endoscopic procedure, using the USE system, is safe and effective for primary and recurrent CTS in haemodialysis patients.

Measurement of carpal canal and median nerve pressure in patients with carpal tunnel syndrome.

Carpal tunnel syndrome is a compression neuropathy wherein the median nerve is compressed inside of the carpal canal. Its diagnosis is made clinically, electrophysiologically, and sometimes by carpal canal pressure measurement. The objective of surgical management of this condition is the decompression of the median nerve. We usually measure carpal canal pressure preoperatively and postoperatively using a continuous infusion technique for diagnoses as well as for postoperative evaluation of decompression following our Universal Subcutaneous Endoscope system procedure. To evaluate whether our procedure effectively decompressed the median nerve, we measured intraneural pressure preoperatively and postoperatively in the resting position, with active power grip, and in the Okutsu test position. Correlation between the carpal canal pressure and intraneural median nerve pressure was statistically analyzed using the Kendall rank correlation coefficient (n = 157 hands). A significant correlation was present preoperatively in resting position and postoperatively with active power grip and in the Okutsu test position. Because of this correlation, we conclude that our endoscopic operative procedure effectively decompresses the median nerve and that simple carpal canal pressure measurement is sufficient to confirm diagnoses and to evaluate the status of postoperative decompression.