Wrist Flexion Crease Research Articles

Muscular branches from the ulnar artery are the basis for a pedicled partial flexor digitorum superficialis muscle flap.

The feasibility of a pedicled flexor digitorum superficialis muscle flap was studied in 10 fresh cadavers. The number, length and distance from the flexion wrist crease of muscular branches from the ulnar artery in the distal 10 cm of the forearm were recorded. The mean number of muscular branches was 2.7 (range 1-4). The mean distance of the most distal branch was 35 mm (range 26-40) from the proximal wrist flexion crease. Its mean length was 20 mm (range 16-26). A partial muscle flap was raised on the most distal branch and transposed over the median nerve in the distal forearm. Dissection and transposition of this flap were feasible in all specimens. The reliable pattern of muscular branches to the flexor digitorum superficialis allows the elevation of a pedicled partial muscle flap that can cover the median nerve in the distal forearm.Level of evidence: V.

Morphological and radiological features of congenital muscular hypertrophy of the upper limb: experience from a tertiary institution.

Congenital muscular hypertrophy is a rare overgrowth disorder in the phosphatidylinositol-3-kinase related spectrum. In the past 3 years, ten patients with 11 limbs involved were treated in our centre. The aim of the study was to describe the clinical and radiological deformities of these patients. We documented the characteristic clinical morphological changes, such as hypertrophy, loss of wrist flexion, thumb hyperabduction, finger deviation and skin crease changes in the palm. Radiologically, the mean first metacarpal radial deviation angle of the affected side measured 55° (range 34 to 67) compared to the normal contralateral side 42° (range 32 to 53). The mean intermetacarpal space ratio was 1.2 (range 1.1 to 1.4) and the mean palm width ratio was 1.2 (range 1.1 to 1.3). In this study, we were able to further characterize the radiological and morphological changes of congenital muscular hypertrophy of upper limbs, which would be helpful for establishing the diagnosis and monitor treatment of this rare condition.Level of evidence: IV.

Restoration of intrinsic hand function by superficial radial nerve: an anatomical study

BackgroundThe contralateral seventh cervical (cC7) nerve root transfer represents a cornerstone technique in treating total brachial plexus avulsion injury. Traditional cC7 procedures employ the entire ulnar nerve as a graft, which inevitably compromises its restorative capacity.ObjectiveOur cadaveric study seeks to assess this innovative approach aimed at preserving the motor branch of the ulnar nerve (MBUN). This new method aims to enable future repair stages, using the superficial radial nerve (SRN) as a bridge connecting cC7 and MBUN.MethodsWe undertook a comprehensive dissection of ten adult cadavers, generously provided by the Department of Anatomy, Histology, and Embryology at Fudan University, China. It allowed us to evaluate the feasibility of our proposed technique. For this study, we harvested only the dorsal and superficial branches of the ulnar nerve, as well as the SRN, to establish connections between the cC7 nerve and recipient nerves (both the median nerve and MBUN). We meticulously dissected the SRN and the motor and sensory branches of the ulnar nerve. Measurements were made from the reverse point of the SRN to the wrist flexion crease and the coaptation point of the SRN and MBUN. Additionally, we traced the MBUN from distal to proximal ends, recording its maximum length. We also measured the diameters of the nerve branches and tallied the number of axons.ResultsOur modified approach proved technically viable in all examined limbs. The distances from the reverse point of the SRN to the wrist flexion crease were 8.24 ± 1.80 cm and to the coaptation point were 6.60 ± 1.75 cm. The maximum length of the MBUN was 7.62 ± 1.03 cm. The average axon diameters in the MBUN and the anterior and posterior branches of the SRN were 1.88 ± 0.42 mm、1.56 ± 0.38 mm、2.02 ± 0.41 mm,respectively. The corresponding mean numbers of axons were 1426.60 ± 331.39 and 721.50 ± 138.22, and 741.90 ± 171.34, respectively.ConclusionThe SRN demonstrated the potential to be transferred to the MBUN without necessitating a nerve graft. A potential advantage of this modification is preserving the MBUN’s recovery potential.

Endoscopic release of the carpal tunnel using the Agee technique modified by Neumann

Decompression of the median nerve by complete endoscopic release of the transverse carpal ligament (TCL) and the distal antebrachial fascia. Minimization of surgical trauma results in decreased postoperative morbidity and earlier return to work and daily activities. Symptomatic carpal tunnel syndrome. Revision surgery after open or endoscopic procedure, rheumatic diseases. Small transverse incision at the ulnar border of the palmaris longus tendon, and proximal to the distal wrist flexion crease. Exposure and incision of the antebrachial fascia, dilatation of the carpal tunnel and dissection of synovial tissue from the undersurface of the TCL. With the wrist in extension, the endoscopic blade assembly with integrated camera is inserted into the canal. Exposure of TCL and short incision in the middle portion. Gradually, dissection of the distal portion of the TCL then completion by retraction of the blade distally to proximally. Slightly compressive dressing, selfcare on day1 after procedure. More than 25years of experience, more than 8000 treated patients, and 3 documented cases with intraoperative lesions of the median nerve requiring revision. High acceptance and patient satisfaction in AQS1patient-reported surveillance.

Mini-inciziona tehnika u zbrinjavanju sindroma karpalnog tunela

Introduction/Aim: Carpal tunnel syndrome (CST) is the most common cause of upper extremity compressive neuropathy. Until the introduction of endoscopy, the dominant surgical method was classic open surgery. The objective of the paper is to examine the efficacy, safety and economic value of the mini-open carpal tunnel release technique using a longitudinal 2 cm long incision in the carpal region. Methods: The diagnosis was made based on clinical examination, followed by an ENMG. The study includes only patients with idiopathic CTS, while those who have developed CTS as a result of secondary causes have been excluded from the study. All patients were operated on under local anaesthesia, WALANT, without the use of a tourniquet. A longitudinal incision 2 cm long is made in the line of the radial edge of the ring finger, 2-3 cm distal to the wrist flexion crease, immediately proximal of the Caplan cardinal line and ulnar to the thenar crease. Upon cutting through the skin and subcutaneous soft tissue, the superficial fascia is identified and then cut with the same scalpel in the same direction and the same length. The transversal ligament is then identified and carefully incised with a scalpel enough to allow further decompression with the use of scissors. Using standard surgical scissors for the hand, the ligament is cut proximally to the forearm fascia and then distally until a faint crackling sound is heard, which means that the ligament had been completely cut. This must be checked by inserting the Freer elevator proximally and distally to the edge of the ligament. Now it is possible to identify the nerve and accompanying hand flexor tendons. Sutures are placed only on the skin and a roll of gauze is fixed to the wound with an elastic bandage to provide compression. The first check-up is on the very next day and the patient is advised to start doing hand exercises. The sutures are removed 10-14 days after surgery. Results: From January 2018 to December 2019, 35 carpal tunnel decompressions were performed on 30 patients using the mini-open decompression technique and standard surgical scissors. The surgery was performed on 22 patients in the operating room and 8 patients in the infirmary. There were no intraoperative complications. All patients reported no night pain from the very first day after surgery. Pillar pain, incision pain and hand weakness were progressively becoming less pronounced during the next 12 weeks. At the final check-up, only one patient still had pronounced symptoms that required a reintervention. The rest of the patients had completely recovered. Even though the endoscopic procedure for carpal tunnel decompression is constantly evolving, the classic open method and newly developed mini-open carpal tunnel release technique remain the treatments of choice. Conclusion: Our research shows that the mini-open carpal tunnel release technique is a quick, efficient, safe and cheap surgical technique for treating carpal tunnel compressive neuropathy.

Patterns of Ulnar Nerve Arborization in the Palm: Clinical Implications for Nerve Decompression in the Hand and Wrist

Purpose The purposes of this study were to examine variations and frequencies of the arborization patterns and communicating branches of the ulnar nerve in the palm, review existing literature, and relate these findings to nerve decompression in the hand and wrist. Methods The arborization pattern of the ulnar nerve near Guyon canal was examined in 18 cadaver hands and described according to the classification of Murata et al. Communicating branches between the ulnar and median nerves were described according to the classification of Bas and Kleinert. We measured the specific distance from the wrist flexion crease to the origin of the communicating branch and the angle of the communicating branch with the originating nerve. Results In 13 of 18 hands (72%), a type 1 arborization pattern was found; in 4 hands (22%), there was a type 2 pattern; and in 1 hand (6%), a branching pattern not previously described was found. In 11 of 18 hands (61%), a communicating branch was observed between the ulnar and median nerves. The branch ran from the ulnar to the median nerve (type 1) in 10 hands (56%); the connection was plexiform (type 4) in one hand (5.6%). The communicating branch originated at a median distance of 1 mm from the distal edge of the transverse carpal ligament and had a median angle of 42.5° (interquartile range, 40° to 45°). Conclusions Variations in arborization patterns of the ulnar nerve and the existence of communicating branches between the ulnar and median nerves in the palm are common and may lead to the atypical distribution of symptoms and unforeseen risks during hand surgery. Clinical relevance This study provides a comprehensive overview of previous findings and relates these findings to current clinical practice. Knowledge about variations in arborization patterns of the ulnar nerve and communicating branches between the ulnar and median nerves in the palm optimizes diagnoses and minimizes specific surgical risks in hand surgery.

Localisation of the radial nerve at the spiral groove: A new technique

SummaryBackgroundLocalisation of the radial nerve (RN) in the spiral groove by previously reported methods has a wide range and is generalised. The objective of this study was to establish a method unique to a patient to accurately localise the nerve.MethodsThe distance between RN at the midpoint of the spiral groove (D) and the tip of the olecranon (O) was compared with the most distal wrist flexion crease and fingertips on 100 healthy volunteers. The RN was found by ultrasound examination.ResultsThe mean distance from O to D was 16.22 cm (12.5–20.5 ± 1.55), and mean distances from wrist crease (WC) to second, third, fourth and fifth fingertips were 17.79 (14–20 ± 1.28), 18.66 (15–21 ± 1.32), 17.71 (14.5–20.5 ± 1.32) and 15.62 (12.5–20.5 ± 1.34) cm, respectively. With regards to O–D distance, the strongest relationship was obtained for the distance between the fifth fingertip to the WC (r = 0.708, p < 0.001). This relationship was stronger among females than males (p < 0.001).ConclusionThe course of the RN can be easily found at the upper arm by this method, which is unique to a patient.The translational potential of this articleThis study presents a new and individualised approach to accurately predict the location of the RN in the spiral groove. This method is clinically relevant and can be used to guide the surgical explorations or expedite interventional methods.

Ultrasound-assisted surgical release of carpal tunnel syndrome: Results of a pilot open-label uncontrolled trial conducted outside the operating theatre

ObjectiveTo confirm the feasibility of ultrasound-assisted surgical release of carpal tunnel syndrome in the interventional radiology room. Materials and methodsStudy involving 39 patients suffering from carpal tunnel syndrome confirmed by electromyogram and unresponsive to medical treatment. The patients were recruited via orthopedic surgery and rheumatology consultations and were operated on in the interventional radiology room under local anesthesia. A single approach was used, at the wrist flexion crease. Patients were monitored over a 90-day period. This is a descriptive open-label uncontrolled study. ResultsFifteen men and 24 women, aged between 21 and 86 years, were included, 23 of whom were in work. The mean surgical procedure time was of 19.0±4.6minutes; the mean room occupancy time was of 38.0±8.1minutes and the mean volume of local anesthetic used was of 14.7±2.3 cc. The score for pain, formication and discomfort experienced in the hand was significantly reduced by day 15 (49.1±21.1 vs. 23.5±19.5; P<0.001). Eight patients continued to present with paresthesia on day15 and only 3 by day 30. Four patients had returned to work by day 15, 10 patients considered that they could have resumed work within an average of 9.9±4.9 days after the procedure. Twenty-five patients estimated that they could resume their daily activities within a mean period of 7±3.9 days. No postoperative complications related to the procedure were observed. ConclusionAccording to the results of this study, ultrasound-assisted surgical release of carpal tunnel syndrome performed outside the operating theatre seems to be effective and well-tolerated.

Mini-open versus extended open release for severe carpal tunnel syndrome.

This study aims to compare surgical outcomes of severe carpal tunnel syndrome (CTS) treated with mini-incision versus extensile release. The method employed in this study was a retrospective review of patients with severe CTS, defined by electrophysiologic studies showing non-recordable distal sensory latency of the median nerve. Patients underwent either a mini-incision (2cm) release of the transverse carpal ligament (group 1) or extensile release proximal to the wrist flexion crease (group 2). Exclusion criteria included prior carpal tunnel release, use of muscle flap, multiple concurrent procedures, or a prior diagnosis of peripheral neuropathy. Group 1 included 70 wrists (40 females, 30 males). Group 2 included 64 wrists (35 females, 29 males). Reported outcomes included pre- and post-operative grip strength as well as Boston Carpal Tunnel Questionnaires (BCTQ). Patients in group 1 had a 22.6% increase in grip strength postoperatively (4.5months ± 5.0), while patients in group 2 had a 59.3% increase (10.0months ± 6.9). BCTQ surveys from group 1 (n = 46) demonstrated a symptom severity score of 12.93 and functional status score of 9.39 at an average follow-up of 41.9 ± 10.6months. Group 2 (n = 42) surveys demonstrated averages of 12.88 and 9.10 at 43.1 ± 11.6months. One patient in the mini-incision cohort required revision surgery after 2years, while no patient in the extended release cohort underwent revision. No significant differences between the two procedures with regard to patient-rated symptom severity or functional status outcomes were found. Both techniques were demonstrated to be effective treatment options for severe CTS.

The Effect of Short Arm Cast Length on Forearm Rotation

To compare ranges of active forearm pronation and supination with subjects wearing short arm casts of different lengths. Forty right-handed healthy volunteers (20 men and 20 women) with an average age of 39 years (range, 26-58 y) were recruited. A goniometer with a circular plate and a handle connected to the scale indicator was used to measure forearm pronation and supination without a cast and with 3 different lengths of short arm cast. All casts extended from just proximal to the volar and dorsal aspects of metacarpophalangeal joints, and continued to either 2.5 cm distal to elbow flexion crease or 5 cm distal to the elbow flexion crease, or to the proximal one-third position between the wrist flexion crease and the elbow flexion crease. Compared with no immobilization, the longest of the 3 constructs reduced active forearm rotation by 62%, whereas the cast to 5 cm from the elbow flexion crease reduced rotation to 50%, and the cast to the proximal one third of the way between the wrist and elbow flexion crease reduced rotation by 32%. Active forearm rotation was significantly dependent on cast length, and reductions in active forearm rotation were positively correlated with cast length. Limitation of active forearm rotation by a short arm cast is positively correlated with cast length. When a short arm cast is used to limit wrist motion and forearm rotation, it is better to extend it proximally but not to impinge on the antecubital fossa, where skin breakdown may occur.

Can palmar creases serve as landmarks for the deeper neuro-vascular structures?

Purpose The aim of this study was the examination of the superficial anatomy of palmar creases and their relation to deeper neuro-vascular structures.MethodsFour creases: distal wrist flexion crease, thenar crease, proximal palmar crease and distal palmar crease were evaluated with reference to the following structures: palmar cutaneous branch of median nerve, palmar cutaneous branch of ulnar nerve, the nerve of Henle, transverse palmar branches from ulnar nerve, recurrent motor branch of median nerve, radial proper palmar digital nerve to the index and the ulnar proper palmar digital nerve to the thumb, Berrettini’s communicating branch, ulnar nerve and artery, superficial palmar arch. We performed dissections of 20 cadaveric upper limbs derived from a homogenous Caucasian group. In our study we measured the location of surgically important structures with reference to palmar skin creases.Results Among the other observations we noticed that the palmar cutaneous branches of the median and ulnar nerves were located at least 0.5 cm away from the thenar crease. The superficial palmar arch was found between the thenar and proximal palmar crease and never crossed the proximal or distal palmar creases.ConclusionsThese anatomical dissections will provide reference material for further ultrasound studies on the arrangements of neuro-vascular structures in reference to superficial palmar creases.

Transverse Ulnar Forearm Flap

The transverse ulnar forearm flap (TUFF) was used to reconstruct different recipient sites in 5 consecutive cases based on the specific requirement for a small thin, hairless flap with a long pedicle. Recent studies have clarified the benefits of the ulnar forearm flap: a less inconspicuous donor site and a primary donor site closure with a radially based fasciocutaneous flap. The TUFF is designed with its long axis transverse and distal margin parallel with a wrist flexion crease. An incision is extended proximally along the ulnar artery pedicle as far as the takeoff from the brachial artery if needed. After elevating the ulnar forearm flap in the standard fashion, transverse primary closure of the donor site is obtained by elevating a large volar forearm fasciocutaneous flap based on the radial artery and advanced distally with a V-Y advancement. Any dog ear is tailored, and the wrist is flexed at 30 degrees. All TUFF and radial fasciocutaneous flaps survived completely without partial or total losses or ischemic hand complications. One patient had a wide scar at the proximal forearm Y junction that was revised. Two-point fingertip discrimination and range of motion were satisfactory. The TUFF is a synthesis of variations of previously described forearm flap techniques and provides a specialized flap in situations where small, thin, pliable, hairless fasciocutaneous flap with a long vascular pedicle are necessary. These characteristics make it appropriate in orbital reconstruction and palatal surgery.

Nerve Tumors

A 58-year-old right-handed woman was referred for a 5-year history of numbness in the left median nerve distribution and a slowly growing volar wrist mass. Her examination was notable for a nontender, firm, midline mass extending from the proximal wrist flexion crease to the distal palmar crease. Phalen's test and Tinel's tests were positive. Semmes-Weinstein monofilament testing was 3.61 in the median nerve distribution and 2.83 in the remainder of the hand. Electrophysiological tests demonstrated muscle denervation within the thenar muscles and undetectable motor and sensory latencies. Magnetic resonance imaging (MRI) revealed median nerve enlargement extending from the distal forearm to the distal metacarpal region with fatty infiltration. Educational Objectives •State the most common types of peripheral nerve sheath tumors. •Discuss the differences between neurofibromas and schwannomas. •List the schwannoma characteristics associated with permanent neurologic dysfunction following excision via intracapsular enucleation. •Describe risk factors associated with elevated risk for peripheral nerve tumors. •Summarize the MRI findings consistent with a malignant peripheral nerve tumor. Earn up to 2 hours of CME credit per JHS issue when you read the related articles and take the online test. To pay the $20 fee and take this month’s test, visit http://www.assh.org/professionals/jhs. •State the most common types of peripheral nerve sheath tumors. •Discuss the differences between neurofibromas and schwannomas. •List the schwannoma characteristics associated with permanent neurologic dysfunction following excision via intracapsular enucleation. •Describe risk factors associated with elevated risk for peripheral nerve tumors. •Summarize the MRI findings consistent with a malignant peripheral nerve tumor. Earn up to 2 hours of CME credit per JHS issue when you read the related articles and take the online test. To pay the $20 fee and take this month’s test, visit http://www.assh.org/professionals/jhs. Journal CME QuestionsJournal of Hand SurgeryVol. 35Issue 9Preview Full-Text PDF

Super-Thinned Iliac Flap for Major Defects on the Elbow and Wrist Flexion Creases

Four free iliac flaps were used to treat or prevent flexion contracture at the elbow or wrist flexion crease. Flap size ranged from 13 x 6 cm to 18 x 8 cm. Two flaps were used for primary coverage, and the other 2 flaps were used to treat established flexion contractures. All flaps survived without vascular complications. Full range of motion was obtained at the elbow and 40 degrees of active extension was obtained at the wrist. The flap has a very thin dermis with minimal panniculus that can be thinned as required, making it ideal to cover flexion creases. Despite the fact that anatomic variations are common in the inguinal region, the flap can be expeditiously and safely elevated. If needed, pedicle length can be up to 8 to 10 cm. The donor site is comparable with that of a full-thickness skin graft harvested from the groin. The donor artery, however, can be very small.

Cross-Sectional Area of the Carpal Canal Proximal and Distal to the Wrist Flexion Crease

The purposes of this study were as follows: (1) to locate the position of the distal wrist flexion crease with respect to the carpal bones, specifically the proximal pole of the capitate, and (2) to determine the cross-sectional area of the carpal canal proximal and distal to the wrist flexion crease to enable us to determine whether or not there is a focal area of narrowing that would provide an anatomic basis for the proximal extent of carpal tunnel release. This study had 2 parts. The first part was a plain radiographic study of 21 uninjured wrists in 12 volunteers that defined the position of the distal wrist flexion crease with respect to the carpus. The second part was a magnetic resonance imaging study of 13 wrists in asymptomatic volunteers that measured the cross-sectional area of the carpal canal proximal and distal to the wrist flexion crease. In 19 of 21 wrists the distal wrist flexion crease was within 2 mm of the proximal pole of the capitate. We noted a gradual increase in the area of the carpal canal moving proximal from its narrowest point. There was no significant increase in area until approximately 23 mm proximal to the narrowest point. We noted no focal area of narrowing in the cross-sectional area of the carpal canal either proximal or distal to the wrist flexion crease.

Carpal tunnel release through a limited skin incision under direct visualization using a new instrument, the carposcope.

A new surgical technique with a set of instruments has been developed for the release of carpal tunnel. The technique allows division of the transverse carpal ligament through a short transverse skin incision (1.5 to 2 cm) of the wrist flexion crease under direct visualization. The technique has been used on 237 patients for 275 cases of carpal tunnel release (38 bilateral). Following the release, median time to activities of daily living was 7 days for 60 compensation patients and 6 days for 193 noncompensation patients (22 patients provided no information on the activities of daily living). The median time to return to work was 49 days for 51 compensation workers and 20 days for 64 noncompensation workers. The overall relief rate of preoperative symptoms was 86 percent (90 percent for noncompensation patients, 82 percent for compensation patients). There were no intraoperative complications among our studies of 275 cases by two surgeons (176 cases by the senior author). The described technique of carpal tunnel release is a useful alternative to open carpal tunnel release because of decreased short-term postoperative morbidity and to the endoscopic carpal tunnel release because of the simplicity and the lower cost of instrumentation.

The lumbrical muscle flap: Anatomic study and clinical application

This article describes the anatomy and clinical application of the lumbrical muscle flap. Anatomic and radiologic studies were performed in 20 fresh human cadaver hands injected with latex-lead-oxide solution. Only the 2 radial lumbrical muscles were found suitable for flap transposition. The vascular supply of the first and second lumbrical muscles is from branches originating in the superficial palmar arch and from the common palmar digital artery, respectively. The dominant branches invariably enter the muscle bellies at the junction of their proximal and middle thirds. Pedicled on these vessels, the lumbrical muscles can be transposed to reach the entire palm, up to the wrist flexion crease. The clinical use of the first and second lumbrical muscle flaps in 2 patients demonstrated the value of these flaps for coverage of the median nerve and its palmar branches.

Microsurgical carpal tunnel release.

The author reports on a series of 482 patients who underwent primary carpal tunnel release (CTR) surgery beginning in 1987. Two hundred twenty-five patients underwent CTR in the right hand, 169 patients underwent CTR in the left hand, and 88 patients underwent bilateral CTR surgery, for a total of 570 hands. These surgeries were performed on an outpatient basis. After application of a local anesthetic, a microsurgical technique using a 2-cm longitudinal incision that did not cross the wrist flexion crease was accomplished. In five patients the recurrent thenar branch exited through the middle or ulnar portion of the ligament and this branch was preserved in all five. Perioperative complications included stitch abscesses in nine hands (2%), which were managed on an outpatient basis; deep wound infections occurred in three hands (0.5%) and these patients were admitted for intravenous antibiotic administration and wound care. One steroid-dependent patient suffered wound dehiscence due to a fall and the wound was primarily repaired. One patient required a second minor procedure to remove a retained suture. Two patients developed "trigger finger" 6 months postoperatively. The mean time until return to work for those patients not receiving Workers' Compensation was 3 weeks and for those receiving Workers' Compensation it was 6.5 weeks. Complete disappearance of painful dysesthesias occurred in 431 (89%) of 482 patients. Marked improvement occurred in another 33 (7%) patients, yielding an overall improvement rate of 96%. Motor improvement was noted in 438 (96%) of 454 patients with preoperative motor weakness. Bilateral symptoms resolved on the contralateral side following unilateral surgery in seven patients. Fifteen patients (12 of whom were receiving Workers' Compensation) experienced persistent dysesthesias and/or incision pain and did not return to work. An additional eight procedures were performed in patients who had previously undergone surgery at another institution; four showed no evidence of their transverse carpal ligament being sectioned. Five of the eight patients undergoing reexploration noted postoperative improvement in their symptoms. Finally, 14 (3%) patients presented 1 to 5 years postsurgery with thenar/hypothenar pain. These patients have responded to local steroid injections and are being followed by a hand surgeon. The reimbursement of the surgeon's fee is 253.00 dollars from Medicaid, 360.00 dollars from Medicare, and 560.00 dollars from preferred provider insurance. The mean total time in the outpatient operating room is 35 to 40 minutes. The outcome and time to return to work are equal, if not superior, to those reported for endoscopic CTR surgery. Microsurgical CTR is thought to be safer and probably more cost-effective.

Carpal tunnel release through a limited skin incision under direct visualization using a new instrument, the carposcope.

A new surgical technique with a set of instruments has been developed for the release of carpal tunnel. The technique allows division of the transverse carpal ligament through a short transverse skin incision (1.5 to 2 cm) of the wrist flexion crease under direct visualization. The technique has been used on 237 patients for 275 cases of carpal tunnel release (38 bilateral). Following the release, median time to activities of daily living was 7 days for 60 compensation patients and 6 days for 193 noncompensation patients (22 patients provided no information on the activities of daily living). The median time to return to work was 49 days for 51 compensation workers and 20 days for 64 noncompensation workers. The overall relief rate of preoperative symptoms was 86 percent (90 percent for noncompensation patients, 82 percent for compensation patients). There were no intraoperative complications among our studies of 275 cases by two surgeons (176 cases by the senior author). The described technique of carpal tunnel release is a useful alternative to open carpal tunnel release because of decreased short-term postoperative morbidity and to the endoscopic carpal tunnel release because of the simplicity and the lower cost of instrumentation.

The cutaneous innervation of the palm: An anatomic study of the ulnar and median nerves

Twenty-five fresh-frozen cadaveric hands without obvious deformity were dissected using 3.5x loupe magnification. Median and ulnar nerves were identified in the proximal forearm and dissected distally to the midpalm. Cutaneous branches of median and ulnar nerves were described relative to an incision for carpal tunnel release. The palmar cutaneous branch of the median nerve was present in all 25 specimens. In a single specimen, the palmar cutaneous branch of the median nerve was isolated as it crossed the incision, and in another two specimens, the terminal branches of the nerve were identified at the margin of the incision. In 4 hands, a classic palmar cutaneous branch of the ulnar nerve was found an average of 4.9 cm proximal to the pisiform. In 10 specimens, a nerve of Henle arose an average of 14.0 cm proximal to the pisiform and traveled with the ulnar neurovascular bundle to the wrist flexion crease. In 24 specimens, at least one-usually multiple-transverse palmar cutaneous branch was identified originating an average of 3 mm distal to the pisiform within Guyon's canal. The origin and destination of these nerves was highly variable. In 16 specimens, an incision in the axis of the ring finger would likely have encountered at least one branch of the ulnar-based cutaneous innervation to the palm. Cutaneous branches of the ulnar nerve would be expected to cross the line of dissection frequently during open carpal tunnel release. Decreased levels of discomfort in patients undergoing endoscopic and subcutaneous types of carpal tunnel release may be in part due to the preservation of the crossing cutaneous nerves with these procedures.