In vivo flexor tendon forces increase with finger and wrist flexion during active finger flexion and extension.

The effects of different hand motions and positions used during early protected motion rehabilitation on tendon forces are not well understood. The goal of this study was to determine in vivo forces in human flexor digitorum profundus (FDP) and flexor digitorum superficialis (FDS) tendons of the index finger during active unresisted finger flexion and extension. During open carpal tunnel surgery (n = 12), flexor tendon forces were acquired with buckle force transducers, and finger positions were recorded on video while subjects actively flexed and extended the fingers at two different wrist angles. Mean in vivo FDP tendon forces varied between 1.3N +/- 0.9 N and 4.0 N +/- 2.9 N while mean FDS tendon forces ranged from 1.3N +/- 0.5 N to 8.5 N +/- 10.7 N. FDP force increased with active finger flexion at both wrist angles of 0 degrees or 30 degrees flexion. FDS force increased with finger flexion when the wrist was in 30 degrees flexion, but was unchanged when the wrist was in 0 degrees of flexion. Tendon forces were similar regardless of whether the fingers were moving in the flexion or extension direction. Active finger flexion and extension with the wrist at 0 degrees and 30 degrees flexion may be used during early rehabilitation protocols with limited risk of repair rupture. This risk can be further decreased for a FDS tendon repair by reducing wrist flexion angle.     

A new dynamic splint for postoperative treatment of flexor tendon injury

This dynamic splint lessens resistance to finger extension and increases the arc of motion through full passive flexion of the injured fingers. Rubber bands run from the tips of the injured fingers under a spring-loaded roller bar at the metacarpophalangeal joint level to a coiled lever at the distal flexor surface of the forearm. The wrist is positioned in 45 degrees of flexion with 40 degrees to full flexion of the metacarpophalangeal joints and full flexion to full extension of the interphalangeal joints. We retrospectively compared patients treated in the new and traditional splints. Patients with coexisting fractures, extensor tendon injury, and insufficient follow-up were excluded. By use of Strickland's modified criteria in evaluating 36 patients treated in the new splint, 35 of 46 fingers with zone II tendon injury (76.1%) had excellent and 11 (23.9%) had good total active motion; none had fair or poor results or ruptures. Results were significantly better than after treatment in the traditional splint.     

Zone I flexor tendon rehabilitation with limited extension and active flexion.

This article describes an immediate active motion protocol for primary repair of zone I flexor tendons treated with tendon to tendon, or tendon to bone repair, and reviews clinical results. A rehabilitation protocol is proposed that will limit excursion of the zone I repair by blocking full distal interphalangeal (DIP) extension and by applying controlled active tension to both the unrepaired flexor digitorum superficialis (FDS) and the repaired flexor digitorum profundus (FDP). The rehabilitation technique utilized a dorsal protective splint with a relaxed position of immobilization with 30 degrees of wrist flexion, 40 degrees of metacarpophalangeal (MP) joint flexion, and a neutral position for the proximal interphalangeal (PIP) joints without dynamic traction. In addition, within the confines of the dorsal splint, the involved DIP joint was splinted at 40-45 degrees to prevent DIP joint extension during the early wound healing phases. Relaxed composite flexion was used to apply active tension to both the uninjured FDS, and the repaired FDP. This technique applies excursion of approximately 3 mm to the zone I tendon in a limited arc (45-75 degrees). The modified position of active flexion applies low loads of force (< 500 g), even with drag considered. This technique is supported by previous mathematical studies of excursion and internal tendon force, and clinical experience. Forty nine cases treated over a 10-year period were reviewed, and eight were excluded for incomplete follow-up. The use of this protocol for 41 zone I flexor digitorum profundus repairs by 12 different surgeons using varied surgical techniques was evaluated. None of the tendon to tendon repairs used more than two suture strands for the core repairs. Mean total active range of motion was 142 degrees (PIP 95 degrees plus DIP 47 degrees), or 81% of normal. Three tendons ruptured in non-protocol-related incidents and were excluded from the study. Results from this clinical study support the use of limited DIP extension combined with active tension with conventional repair in zone I.     

Flexor tendon repair in zone II with 6-strand techniques and early active mobilization

PURPOSE: There are many biomechanic studies of 6-strand suture techniques for active mobilization, but few reports have described the clinical outcome in zone II flexor tendon lacerations. We discuss the clinical results of zone II flexor tendon repair using 2 of these techniques followed by controlled early active mobilization. METHODS: Six-strand sutures using the number 1 technique by Yoshizu or a triple-looped suture technique were used to repair flexor tendons in 27 fingers from 21 consecutive patients. Fingers were mobilized by combining active extension and passive or active flexion in a protective splint for the first 3 weeks after surgery. The follow-up period averaged 13 months. RESULTS: Based on the original Strickland criteria, the results were excellent in 17 fingers, good in 9, and fair in 1. The average flexion was 62 degrees for distal interphalangeal joints and 91 degrees for proximal interphalangeal joints. None of the repaired tendons ruptured. CONCLUSIONS: The 6-strand flexor tendon suture technique followed by controlled active mobilization protected with a dorsal splint is safe, produces no ruptures, and achieves very good results in zone II flexor tendon laceration repair. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic, Level II.     

Optimizing independent finger flexion with zone V flexor repairs using the Massachusetts General Hospital flexor tenorrhaphy and early protected active motion

PURPOSE: Independent FDS action has been cited to be problematic with repair of multiple tendons in zone V owing to adhesion formation between the flexor digitorum superficialis (FDS) and the flexor digitorum profundus (FDP) tendons. Of the several described flexor repair techniques the ideal tendon repair should be strong enough to allow for early active motion to minimize adhesion formation and maximize tendon healing. Biomechanical studies have proven the Massachusetts General Hospital (MGH) repair to be strong enough to allow for early active motion. The purpose of this study was to examine the use of the MGH technique for zone V flexor tendon injuries to allow for early protected active motion to achieve independent finger flexion through better differential gliding of the tendons. METHODS: We performed a retrospective review 168 zone V finger flexor tendon repairs for 29 patients performed consecutively over 4 years when early active motion was not contraindicated. The same early protected active motion protocol was used for all of these patients. We reviewed total active motion, independent flexion, rupture, and need for tenolysis. These injuries involved 103 FDS and 65 FDP tendons to 103 fingers. The median follow-up period was 24 weeks. Of these 29 patients 19 were men and 10 were women. The average patient age was 28 years. RESULTS: The total active motion for these zone V repairs was 236 degrees +/- 5 degrees Overall 97 of 103 digits attained good to excellent function and 88 of 103 developed some differential glide. One of these patients required a tenolysis. Three repairs ruptured in 1 patient owing to suture breakage that was associated with noncompliance with the dorsal extension block splint. CONCLUSIONS: Our retrospective review of 168 consecutive flexor tendon repairs showed that the MGH technique allowed for early protected active motion, which provided good to excellent functional outcomes with 88 of 103 developing independent finger flexion at an acceptably low complication risk.     

Relative motion flexion following zone I-III flexor tendon repair: Concepts,evidence and practice.

Study DesignNarrative review and case series.IntroductionThe relative motion approach has been applied to rehabilitation following flexor tendon repair. Positioning the affected finger(s) in relatively more metacarpophalangeal joint flexion is hypothesized to reduce the tension through the repaired flexor digitorum profundus by the quadriga effect. It is also hypothesized that altered patterns of co-contraction and co-inhibition may further reduce flexor digitorum profundus tension, and confer protection to flexor digitorum superficialis.MethodsWe reviewed the existing literature to explore the rationale for using relative motion flexion orthoses as an early active mobilization strategy for patients after zone I-III flexor tendon repairs. We used this approach within our own clinic for the rehabilitation of a series of patients presenting with zone I-II flexor tendon repair. We collected routine clinical and patient reported outcome data.ResultsWe report published outcomes of the clinical use of relative motion flexion orthoses with early active motion, implemented as the primary rehabilitation approach after zone I-III flexor digitorum repairs. We also report novel outcome data from 18 patients.DiscussionWe discuss our own experience of using relative motion flexion as a rehabilitation strategy following flexor tendon repair. We explore orthosis fabrication, rehabilitation exercises and functional hand use.ConclusionsThere is currently limited evidence informing use of relative motion flexion orthoses following flexor tendon repair. We highlight key areas for future research and describe a current pragmatic randomized controlled trial.     

Immediate active mobilisation after flexor tendon repairs in Verdan's zones I and II. A prospective study of 20 cases

The authors report their experience with early active mobilisation after repair of complete sections of the flexor tendons within the digital tendon sheath. This is a prospective study carried out over 2 years and represents 20 repairs. The tendons were repaired using a double-loop looking suture of Tsuge (with PDS 4/0) associated with a peritendinous overrun using Prolene 6/0 via a volar Bruner-type incision. Post-operatively, a plaster splint holding the wrist in 30 degrees of flexion, the MP joints in 90 degrees of flexion and allowing complete active flexion of the finger protected the suture site. As soon as the dressings could be reduced (the 5th day post-operatively), the patient was encouraged to actively and synchronously flex all the fingers together as many times as possible during the day. After removal of the plaster splint at one month, the patients were entrusted to a physiotherapist with a view to regain full extension of the wrist and the fingers. We did not note a single case of breakdown of the repair. The mean active mobility (TAM according to Strickland) of the repairs in zone I was of the order of 70% while that for repairs in zone II was 85%. Immediate active mobilisation was not found to compromise, in any way, the results of associated digital nerve repairs. Despite the modest results, this simple-to-understand protocol is directed at present for injuries with a poor initial prognosis (contused and lacerated tendons, associated fractures, and non-motivated patients). Improvement in the quality of suture material should, in future, extend the indications for immediate active mobilisation to all fresh sutures of the flexor tendons.     

Transfer of the pronator teres tendon to the tendons of the flexor digitorum profundus in tetraplegia

In eleven patients who had traumatic tetraplegia, the pronator teres tendon was transferred to the flexor digitorum profundus tendons to restore active flexion of the fingers. At the same time, in ten of these patients the tendon of the brachioradialis was transferred to the tendon of the flexor pollicis longus, and in the eleventh patient the brachioradialis tendon was transferred to the tendon of the flexor digitorum superficialis of the small finger, to restore pinch. The average time between injury and operation was thirty-four months. The average length of follow-up after operation was thirty-four months. Ten patients gained functional active flexion of the fingers, and they reported improved performance of activities of daily living. When the wrist was in 30 degrees of extension, the average active grasp strength was twenty-one millimeters of mercury and the average key-pinch strength was 2.2 kilograms. The average active flexion of the fingers from the resting position, measured from the tip of the finger to the distal palmar crease, was 1.5 centimeters. Only one patient did not gain active flexion of the fingers. Of the entire group, this patient had the least function of the hand on preoperative evaluation; retrospectively, he seemed to be a poor candidate for operation, since the strength of the pronator teres muscle and the sensibility of the hand were insufficient for useful function. We concluded that, in selected tetraplegic patients, transfer of the pronator teres tendon to the flexor digitorum profundus tendons provides useful active flexion of the fingers.     

Effects of tension direction on strength of tendon repair

We investigated changes of tensile strength in tendon repair according to tension direction. Thirty-six fresh-frozen digital flexor tendons were divided into 4 groups with 9 tendons each. The tendons were repaired by the modified Kessler method. Sutured tendons were pulled against pulleys at angles of 0 degrees, 30 degrees, 60 degrees, and 90 degrees to the direction of the pull of the testing machine in the 4 groups, respectively. The repaired tendons were tested in a tensile machine to determine 2-mm gap formation force and ultimate strength of the tendons. The 2-mm gap formation force and ultimate strength in the tendons pulled at 0 degrees were statistically higher than those in the tendons pulled at 30 degrees, 60 degrees, and 90 degrees. The 2-mm gap formation force of the tendons pulled at 30 degrees, 60 degrees, and 90 degrees was 86% +/- 10%, 73% +/- 9%, and 64% +/- 8% of that at 0 degrees, respectively. Ultimate strength of tendons pulled at 30 degrees, 60 degrees, and 90 degrees was 89% +/- 9%, 82% +/- 11%, and 76% +/- 8% of that at 0 degrees, respectively. Values of the 2-mm gap formation force and ultimate strength were statistically the lowest in the group with a pulling angle of 90 degrees. There was no statistically significant difference in repair strength between tendons tested at 0 degrees and those in the model without pulleys. The strength of tendon repair changed considerably according to direction of tension added to the tendons. The gap formation force and ultimate strength decreased as angles of tension increased. The results imply that a repaired tendon will be weakened as the finger is increasingly flexed. The decrease in repair strength should therefore be considered in planning a tendon suture to tolerate active finger flexion and a tendon motion protocol after primary tendon repair.     

Effect of synergistic wrist motion on adhesion formation after repair of partial flexor digitorum profundus tendon lacerations in a canine model in vivo.

BACKGROUND: Therapy employing passive finger flexion and active finger extension with the wrist fixed in flexion is commonly used after flexor tendon repair. However, this method of rehabilitation may not produce full tendon excursion because of buckling of the tendon within its sheath with passive flexion. Studies of cadavera suggest that the use of synergistic wrist and finger motion may improve tendon gliding. The purpose of this study was to assess the effects of passive digital motion, performed with either wrist fixation or synergistic wrist motion, on adhesion and gap formation after flexor tendon repair. METHODS: Sixty-six dogs were randomly allocated to two groups. In each group, two flexor digitorum profundus tendons of one forepaw were partially (80%) lacerated and then repaired with a modified Kessler suture. In each group, a different postoperative therapy (wrist fixation or synergistic motion) was performed twice daily. The dogs were killed at one week, three weeks, or six weeks after surgery, and the repaired tendons were evaluated to determine the adhesion grade and adhesion breaking strength. RESULTS: The synergistic motion group had a significantly lower adhesion grade and significantly less adhesion breaking strength than the wrist fixation group at three and six weeks (p < 0.05). At one week, there was no significant difference between the two therapy groups (p > 0.05). CONCLUSIONS: Passive digital flexion and extension with synergistic wrist motion was an effective therapy after repair of partial zone-2 lacerations in a canine model.     

The effect of vincular injury on the results of flexor tendon surgery in zone 2

From a consecutive series of 82 fingers (69 patients) that sustained flexor tendon lacerations in zone 2, 47 fingers (39 patients) had the status of the vincular system determined during primary repair. The vincula were intact in 22 fingers and not intact in 25. Total active motion (TAM) after rehabilitation and before a reconstructive procedure, such as repair of a rupture, tenolysis, or grafting of a tendon, was the end point of the study. The overall mean TAM was 196 degrees. The mean TAM was 222 degrees for fingers with intact vincula and 176 degrees for fingers with vincula not intact (p less than 0.01). There were no statistical differences between the two groups regarding surgical results when the number of tendons injured per finger and sheath closure were analyzed. This study suggests that the integrity of the vincular system is a determinant of end result TAM and flexor tendon lacerations in zone 2.     

Early dynamic splinting for extensor tendon injuries

Extensor tendon injuries are traditionally splinted with no motion for 3 to 4 weeks after repair. This may result in limitation of flexion because of extensor tenodesis at the site of repair. To prevent this, we used a dynamic splinting program opposite to the one that is used for flexor tendon repair, with an outrigger splint holding the fingers in extension and allowing full active flexion. Fifty-two patients who had extensor tendon repairs in the area from the wrist to the middle of the proximal phalanx were treated. Motion was begun 2 to 5 days after repair and was continued for approximately 5 weeks. No tendon ruptures occurred, and all patients recovered full flexion.     

Repair of flexor carpi radialis tendon laceration at the wrist in a professional ice hockey player

The flexor carpi radialis is a wrist flexor and radial deviator with half the relative strength of flexor carpi ulnaris. In the majority of patients, the flexor carpi radialis tendon is expendable and is routinely used for various reconstructive procedures about the hand and wrist. Isolated flexor carpi radialis lacerations at the wrist are rare. Flexor carpi radialis tendon ruptures, which have been reported in association with distal radius fractures, longstanding osteoarthritis, and percutaneous treatment of scaphoid fractures, are usually treated non-operatively. We report a case of a traumatic laceration of the flexor carpi radialis tendon at the wrist in a professional ice hockey player. Surgical repair and rehabilitation using established principles for intrasynovial flexor tendon repair allowed return to sport at the professional level in 2 months.Tension-free core suture repair was performed with a modified-Kessler, 4-strand repair using a double-stranded 4-0 Supramid suture. A running epitendinous suture was then placed around the circumference of the tendon with 6-0 Prolene. Immobilization of the wrist in 20° of flexion was maintained for 2 weeks. Full active and passive digital motion was allowed immediately postoperatively and continued throughout the rehabilitation. Therapy was initiated at 2 weeks postoperatively with full passive wrist flexion and passive wrist extension to a dorsal block of 20°. At 4 weeks postoperatively, a dorsal splint was fabricated to keep the wrist in neutral. At this time, active extension to a dorsal block of zero and full passive flexion was allowed. Active wrist flexion without resistance was begun at 6 weeks, and full strengthening was allowed at 8 weeks postoperatively. The patient returned to sport at the professional level shortly thereafter. At latest follow-up, the patient has been able to fully participate in professional ice hockey without pain or functional limitation.     

Feasibility of partial A2 and A4 pulley excision: residual pulley strength

We investigated residual digital flexor pulley strengths after 75% excision of the A2 and A4 pulleys. For direct pull-off tests, A2 and A4 pulleys from cadaveric fingers were tested by pulling on a loop of flexor digitorum profundus tendon through the pulley. For functional loading tests, fingers were positioned with the metacarpophalangeal joint flexed to 90 degrees for A2 testing, and with the proximal interphalangeal joint in 90 degrees flexion for A4 testing (with all other joints in full extension). Excision of 75% of A2 and A4 pulleys reduced pulley strengths determined by both testing methods. For the functional loading tests, which are more clinically relevant, mean tendon forces at failure after partial excision of A2 and A4 pulleys were 224 and 131 N respectively, which is sufficient to withstand flexor tendon forces expected during activities of daily living.     

Friction of the gliding surface. Implications for tendon surgery and rehabilitation.

Finger flexor tendon rehabilitation has come a long way, but further advances are possible. Ideally, a healing tendon should move, but under the minimum load necessary to achieve motion. It is possible to design suture repairs that minimize the friction between tendon and sheath while simultaneously maintaining adequate strength to provide a wide margin of safety during therapy. A looped, four-strand modified Kessler repair is a good example of this type of high-strength, low-friction repair. At the same time, rehabilitation methods can also be optimized. A new modified synergistic motion protocol is described in which wrist flexion and finger extension is alternated with wrist and metacarpophalangeal joint extension and finger interphalangeal joint flexion. Based on evidence from basic science studies, the authors hypothesize that this new protocol will deliver more effective proximal tension on the tendon repair than either passive flexion/active extension or synergistic protocols, and may be useful in patients who are not ready for, or are not reliable with, active motion or place and hold protocols. The scientific basis for these new methods is reviewed, and the concept of the "safe zone" for tendon loading, in which tendon motion occurs without gapping of the repair site, is developed.     

Flexor tendon injuries in pediatric patients

PURPOSE: The purpose of this research was to study the incidence and outcome of flexor tendon injuries in pediatric patients. METHODS: A survey of flexor tendon repair in children less than 16 years of age was performed in the City of Helsinki during 2000-2005. A retrospective clinical outcome study of all consecutive 28 patients with 45 involved fingers treated in Children's Hospital was also performed at a mean 38 months (range 12-53 months) after surgery. Active motion program after multistrand tendon repair was used in 33 fingers, cast immobilization in 11 fingers, and elastic bands in 1 finger. Functional and cosmetic subjective result was evaluated by a visual analog scale (VAS, 0-100). Range of motion (ROM) of metacarpophalangeal (MCP) and interphalangeal (IP) joints were measured. Grip strength was recorded. Functional outcome methods of Buck-Gramcko, ASSH, Strickland, and distal interphalangeal joint (DIP) ROM methods were applied. RESULTS: The calculated annual incidence of finger flexor injury per child in Helsinki was 0.036 per 1000. There were no ruptures of the multistrand repairs with active motion program, but three 2-strand core sutures failed within 1 month of the repair. Mean functional and cosmetic VAS scores (all 28 patients) were 87 and 84. Mean ROM ratio of the DIP joint in zone 1 and 2 injuries was 60%, compared to 98% in zone 3 and 5 injuries. Ranges of motion of the proximal interphalangeal (PIP) and MCP joints were practically normal in all patients. There was a discrepancy among the functional outcome scores, with good and excellent results in all 45 fingers (Buck-Gramcko), in 39 fingers (ASSH), in 36 fingers (original Strickland), and in 32 fingers (DIP ROM). CONCLUSIONS: Flexor tendon injuries in children are rare. Both subjective and objective outcomes are generally good. Active motion program is an effective technique after multistrand flexor tendon repair at all levels in children. Range of motion of the DIP joint may be a more effective means of evaluating outcome in pediatric flexor tendon injuries. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.     

The A3 pulley

The tendon-pulley geometry and gliding resistance with and without the A3 pulley were compared in 6 fresh human cadaver fingers. We measured the x-ray images of the distal A2 pulley-tendon angle and proximal A4 pulley-tendon angle with varying degrees of proximal interphalangeal joint flexion between 0 degrees and 120 degrees before and after A3 pulley resection. The gliding resistance of the flexor digitorum profundus tendon under the A2 pulley was also measured at varying tendon-pulley angles. With the A3 pulley removed, the tendon-pulley angle significantly increased compared with the A3 intact state. The gliding resistance between tendon and pulley quadratically increased as the tendon-pulley angle increase from 0 degrees to 60 degrees. These results indicate that the A3 pulley might serve to reduce tendon-pulley gliding resistance by reducing the tendon-pulley angle during finger flexion.     

同种异体肌腱移植修复手部肌腱缺损及指功能重建的疗效

目的探讨应用同种异体肌腱移植修复手部肌腱缺损及重建屈/伸指功能的临床效果。方法 2015年3月至2017年6月间,我科应用同种异体肌腱移植修复手部肌腱缺损18例22指,男12例,女6例;年龄为20-45岁,平均(32.9±8.3)岁。其中伸肌腱缺损6例8指,屈肌腱缺损12例14指。手部伸肌腱缺损范围6-10cm,平均(7.8±2.1)cm;屈肌腱缺损范围5-8cm,平均(6.6±1.3)cm。患者受伤至手术时间为1.5-8个月,平均(5.0±2.8)个月。术前皮肤软组织缺损者行皮瓣转移修复,骨折及骨缺损者行切开复位或植骨内固定术,手部各指间或掌指关节积极行锻炼至被动活动正常,若关节挛缩则行关节松解术。伸肌腱缝合方法采用编织缝合法,屈肌腱缝合方法采用津下套圈或编织缝合法,屈肌腱滑车缺损者在手术同时重建滑车。术后应用抗生素预防感染,伤口定期换药,所有病例均没有使用免疫抑制剂。术后3d-4周伸肌腱移植者以主动屈曲、被动伸直锻炼为主,屈肌腱移植者以主动伸直、被动屈曲锻炼为主,每天活动3次。4周后逐渐增加活动次数及强度,以主动伸屈活动为主。采用国际手外科联合会制定的手指关节总活动度(total active movement,TAM)评定标准评价手部功能。结果 3例术后出现伤口脂肪液化,细菌培养证实为无菌性渗出,予以伤口定期换药后均于术后20d内愈合;其余病例伤口均一期愈合。3例5指因屈肌腱黏连行肌腱松解术。术后随访8-24个月,平均(14.7±4.8)个月。TAM评价结果,优9指,良7指,可3指,差3指,优良率为72.7%。结论同种异体肌腱移植是代替自体肌建移植修复手部肌腱缺损及重建屈/伸指功能的较好方法之一,具有手部功能恢复满意、临床效果显著等优点,但仍存在术后肌腱黏连导致手功能优良率降低,伤口局部存在无菌性渗出导致愈合时间延长等问题,上述问题需在日后的临床应用过程中加以研究解决。     

Operative Behandlung der Krallenhand mittels Lassoplastik

Objectives

The aim is correction of claw deformity of the fingers by intrinsic paralysis.

Indications

Indications are claw deformity of fingers caused by palsy or functional loss of the interosseus or lumbrical muscles as far as the function of the superficial and deep flexors of the finger is intact.

Contraindications

Contraindications are loss or paralysis of finger flexors supplied by the median nerve, fixed extension or flexion contracture of the finger joints, osteoarthritis and other malfunctions of the finger joints, no active flexion and extension of the interphalangeal joints due to compromised tendon gliding. Relative: Upper ulnar nerve palsy with functional loss of the deep flexor of the small and ring finger and possibly of the middle finger.

Surgical technique

The operation technique involves detachment of the flexor digitorum superficialis IV tendon (FDS IV) distal to Camper’s chiasm, division of the tendon into separate strips, interweaving of each tendon strip into the proximal part of the A2 pulley of the affected fingers. In cases of claw deformity of all fingers it may be advantageous to apply the superficial flexor tendon of the long finger in addition to the FDS IV tendon as otherwise the FDS IV tendon has to be divided into four strips resulting in relatively thin tendon strips. If the FDS III and IV tendons are applied, the two strips of the FDS IV tendon are used for lassoplasty of the small and ring fingers and the FDS III tendon for lassoplasty of the middle and index fingers.

Postoperative management

Postoperative management includes immobilization of the operated fingers by a dorsoulnar forearm plaster cast including the metacarpophalangeal joints which are flexed to 70°. After 2 weeks replacement of the cast by a thermoplastic splint for another 4 weeks. During the whole period exercises for the finger and thumb should be carried out.

Results

From April 2003 to June 2012 a total of 17 patients, 8 female and 9 male were surgically treated for claw deformity. The dominant hand was affected in seven patients. The average age was 46?±?15 (22–80) years, the average interval from onset of ulnar palsy to lassoplasty was 61?±?91 (3–288) months. The final follow-up was performed after an average of 42?±?32 (2–112) months. Claw deformity was resolved in 14 out of the 17 patients. The grip strength was on average 58?±?28?% (11–96 %) of the unaffected hand, the mean disabilities of the arm, shoulder and hand (DASH) score was 32?±?18 (5–68) points and the degree of patient satisfaction 7?±?2 (0–10). According to own results and those in the literature lassoplasty can be recommended for the treatment of claw deformity.     

Zone 2 lacerations of both flexor tendons of all fingers in the same patient

Over an eight-year period, the author has treated five males (mean age of 31 years) with clean-cut zone 2 lacerations of both flexor tendons of all fingers using the same surgical technique (profundus only repair using three 'figure of eight' core sutures and proximal venting of the pulley system) and the same postoperative mobilization programme (a dorsal blocking splint with immediate active motion that allowed full extension at the interphalangeal joints). There were no ruptures of the repaired 20 fingers. At final follow-up (mean of 22 months after surgery), the outcome was considered excellent in 12 fingers, good in four fingers and fair in the remaining four fingers by the Strickland-Glogovac criteria. The outcome was similar in all four fingers for every patient supporting the hypothesis of previous studies that the outcome of repair of clean-cut flexor tendon lacerations in zone 2 is related to the psychological and biologic characteristics of the patient.