A novel hook plate fixation technique for the treatment of mallet fractures

The biomechanical properties of the hook plate and pull-out suture in mallet finger fractures: a cadaveric study

A total of 32 cadaveric fingers with bony mallet injuries were fixed using either the hook plate or the pull-out suture technique. The purpose of this study was to assess the immediate postoperative biomechanical responses of the fixation techniques under different load conditions. The fingers were cyclically loaded with a force of 7 N for 3500 cycles and until construct failure. The maximum displacements of the hook plate and pull-out sutures were 0.7 mm and 0.6 mm, respectively (p = 0.556). The stiffnesses of the hook plate and pull-out suture were 1.3 N/mm and 1.1 N/mm, respectively (p = 0.515). The ultimate loads-to-failure for the hook plate and pull-out suture were 64.4 N (interquartile range [IQR] 37.7-77.7) and 44.5 N (IQR 29.7-63.5), respectively (p = 0.094). Both fixation techniques were able to withstand immediate postoperative mobilization without any difference in fracture displacement, construct stiffness or maximum load to failure.

A new custom-made plate preparation method for bony mallet finger treatment and a comparison with extension block technique

OBJECTIVES

In this study, we aimed to describe a new hook plate technique (HPT) and to compare our results with the conventional extension block technique (EBT) with a Kirschner wire (K-wire) for bony mallet finger treatment.

PATIENTS AND METHODS

Between April 2015 and January 2018, a total of 19 patients including 10 who were treated with EBT (7 males, 3 females; mean age: 30.1±7.3 years; range, 17 to 48 years) and nine who were treated with HPT (6 males, 3 females; mean age: 31.7±11.3 years; range, 19 to 42 years) for bony mallet finger with distal interphalangeal (DIP) joint subluxation and/or fracture fragment larger than one-third of distal phalanx (Wehbe-Schneider type 1/b, 2/a, 2/b, 3/a) joint were retrospectively analyzed. The DIP range of motion (ROM), Warren and Crawford scores, time to return to work/daily activity, operation time, the number of fluoroscopy shots, cost and complications were compared.

RESULTS

No significant difference was found in the DIP ROM (p=0.708) and the Warren/Norris and Crawford scores (p=0.217 and p=0.175, respectively) between the two groups. Operation time and material cost were higher with HPT (p=0.006, p=0.001). There was no significant difference in the number of fluoroscopy shots (p=0.344). Although DIP joint motion was started at two weeks in the HPT group and at eight weeks in the EBT group, no significant difference was observed in the time of return to work and normal daily life in both groups (p=0.859). Complications were observed in two patients in the EBT group and in three patients in the HPT group. No significant difference in total complications was observed between the two groups (p=0.666).

CONCLUSION

Bony mallet finger treatment with a custom-made hook plate prepared from 1.3-mm AO plates appeared to be clinically and radiologically similar to EBT. Additionally, HPT had the advantages of allowing early ROM to DIP joint and eliminating the need for a secondary surgery such as K-wire removal. On the other hand, hardware cost with HPT was higher than EBT.

Comparison of single and double dorsal wires in the extension block technique for mallet fractures: Retrospective observational study

Mallet fractures are avulsion fractures of the extensor tendon from the distal phalanx base and often occur due to sudden flexion or axial loading. In this study, we aimed to compare the clinical and radiological results of patients treated with single and double dorsal wires from the dorsal in the extension block method.Patients to whom a single wire from dorsal was applied were assigned to Group 1 (n: 22), and those to whom double wires were applied were assigned to Group 2 (n: 23). Surgical treatment was decided for patients with more than 1/3 of the fracture fragment containing the joint surface and volar subluxation. The range of motion of the distal interphalangeal (DIP) joint was measured with a goniometer. The displacement of the fragment was measured before and after surgery on lateral radiographs. The presence of bridging callus formation on anterior-posterior and lateral radiographs was evaluated for a union.There were 30 male (66.7%) and 15 (33.3%) female patients. The mean age of the patients was 32 years. Radiographic union was obtained in all patients. Pseudoarthrosis was not observed in any patient. The Crawford score was excellent in 13 (28.9%) cases, the score was good in 18 (40%) cases, the scores were moderate in 13 (28.9%) cases, and the score was poor in 1 case (2.2%). There were no complications in 35 (77.8%) cases, dorsal bump complications occurred in 9 cases (20%), and osteoarthritis and dorsal bump complications occurred in 1 (2.2%) case. We did not observe nail deformity, skin necrosis, infection, or fingertip sensitivity. We found similar functional and clinical results between the groups.We recommend using single dorsal wire, as using double dorsal wires requires extra operation time, effort, and fluoroscopy.

Outcomes of an aseptic technique for Kirschner wire percutaneous pinning in the hand and wrist

INTRODUCTION

Kirschner wires (K-wires) have been shown to effectively stabilize fractures of the hand and wrist, but are associated with high infection rates, which may limit its use. Previous literature has attributed the risk of infection to many different aspects of a fixation technique. However, we introduce an approach to percutaneous K-wire pinning to mitigate the risk of infection.

METHODS

Patients undergoing K-wire fixation procedures of the hand and wrist were retrospectively queried. All cases were performed under the same principles of our technique. None of the K-wires were buried, nor bent and were covered with betadine-soaked alcohol pads as pin site dressings. Pins were removed in an outpatient procedure room up to 12 weeks postoperatively and were then assessed for signs of superficial or deep infection.

RESULTS

90 patients were included in this study across a variety of K-wire fixation operations in the hand and wrist. No patients presented with any signs of infection or other complications necessitating postoperative antibiotics, early pin removal, or reoperation.

DISCUSSION/CONCLUSION

The specific guidelines of our technique resulted in no cases of pin site infection, despite a largely underserved patient population. Our low incidence of infection was maintained without the use of prophylactic antibiotics and in patients with long periods of fixation. While the high infection rates in previous literature have often been associated with wires left exposed, the principles of our technique allow for K-wire fixations to be performed percutaneously without burying the wires. This may allow for improved cost and time efficiency, without compromising patient safety.

A Novel Hook Wire Tension Technique for the Treatment of Mallet Fractures: A Comparison with the Extension Block Pinning Technique

We developed a percutaneous surgical technique that allows early mobilization and compression for the treatment of mallet fractures. The aim of this study was to describe this novel technique called the hook wire tension technique (HWTT) and provide a clinical and radiological comparison between HWTT and the extension block pinning technique (EBT) in the treatment of mallet fractures. This retrospective study included 23 mallet fracture patients treated using HWTT and 25 patients treated using EBT. At the final follow-up visit, extension lag and flexion of the distal interphalangeal joint (DIPJ) were measured. DIPJ pain was assessed by the visual analogue scale (VAS) score, and the overall clinical outcomes were graded according to the Crawford criteria. Time to bone healing and osteoarthritis development were assessed radiologically. Complications, including skin necrosis, dorsal prominence and nail deformity, were also compared. The mean follow-up period was 18 months (range: 12-24) in the HWTT group and 19.2 months (range: 12-26) in the EBT group (p = 0.239). There was no statistically significant difference between the two groups in terms of mean extension lag of the DIPJ, mean VAS scores and mean time to bone healing (p > 0.405). The mean DIPJ flexion was greater in the HWTT group compared with the EBT group (p = 0.001). According to the Crawford criteria, outcomes were similar in both groups (p = 0.370). No statistically significant difference was found between the two groups when each complication was compared (p > 0.358). The short-term clinical and functional results of HWTT were found to be similar to those of EBT in the surgical treatment of mallet fractures.

Functional outcomes and complications of hook plate for bony mallet finger: a retrospective case series study

Background

The treatment of mallet fracture using hook plate fixation was first introduced in 2007 and has subsequently shown excellent outcomes. Common complications, such as nail deformity and screw loosening, have also been reported. Very few studies have focused on these common complications or their prevention. In this study, we present the clinical outcomes and complications of our case series and describe the pitfalls and detailed solution of surgical tips to avoid common complications related to this procedure.

Methods

The retrospective case series of 16 patients with mallet fractures who underwent open reduction and hook plate fixation in our hospital from 2015 to 2020 were retrospectively reviewed. Data on extension lag, range-of-motion (ROM) of the distal interphalangeal joint (DIP) joint, the Disabilities of the Arm, Shoulder, and Hand (DASH) score, and surgical complications were collected and analysed. The clinical outcome was graded according to the Crawford mallet finger criteria.

Results

Sixteen patients were included in our analysis. The median DIP extension lag was 0° (range, 0° to 30°) and the median active DIP flexion angle was 60° (range, 40° to 90°). The median DASH score was 0 (range, 0–11.3). Fourteen patients with good and excellent results were satisfied with this treatment. The Complication rate in our patient series was 18%. Common complications reported in articles included wound necrosis, extension lag, nail deformity, and plate loosening.

Conclusions

Despite the fact that the treatment of mallet fracture with hook plate fixation has satisfactory functional outcomes, pitfalls, including iatrogenic nail germinal matrix injury, unnecessary soft tissue dissection, and insufficient screw purchase, were still reported. To avoid complications, we suggest modifications of the skin incision, soft tissue dissection, and screw position.

Clinical outcomes after mini-hook plate fixation for small avulsion fractures around the interphalangeal or metacarpophalangeal joints of the hand

BACKGROUND

Mini-hook plate has been described for the treatment of various small avulsion fragments in the hand. This retrospective study aimed to evaluate clinical outcomes after mini-hook plate fixation in patients with an avulsion fracture around the interphalangeal or metacarpophalangeal joints of the hand.

METHODS

Nineteen patients with avulsion fractures around the interphalangeal or metacarpophalangeal joints of the hand were included in this study. Seven patients had a mallet fracture, and 12 patients had other phalangeal avulsion fractures including central slip, collateral ligament, volar plate, and flexor avulsion fractures. The osseous union and functional outcomes, including finger joint motion, joint stability, pinching strength, and the disabilities of the arm, shoulder, and hand score, were evaluated.

RESULTS

The mean duration of follow-up was 33.8 months. All patients in mallet and other phalangeal avulsion fractures achieved osseous union between the avulsion fragment and phalangeal bone, and there was no joint subluxation. There were no significant differences in the disabilities of the arm, shoulder, and hand scores. However, the patients with mallet fracture have lower mean percentage values of the total active range of motion and pinching strength than other phalangeal avulsion fractures. We abandoned this procedure in mallet fractures because the early results after mini-hook plate fixation in mallet fractures appeared unfavorable.

CONCLUSION

These results suggest that the mini-hook plate fixation can provide sufficient stability and good clinical outcomes in those with phalangeal avulsion fractures. However, the outcomes for mallet fractures were not as good as those for other phalangeal avulsion fractures.

Management of Tendon and Bony Injuries of the Distal Phalanx

Acute tendon and bony injuries of the distal phalanx are challenging injuries because they may result in chronic pain, hypersensitivity, stiffness, and deformity if they are not adequately treated. Flexor tendon avulsions require early surgical repair. Conversely, most extensor tendon injuries and fractures heal well with nonoperative treatment. However, surgery is indicated in selected patients, and meticulous technique is required to achieve good postoperative outcomes. In this article, we outline the pertinent clinical anatomy of the distal phalanx, review the current literature regarding treatment options, and highlight key management points to ensure good clinical outcomes while minimizing complications.

A Trial of the Effect of 2-Step Orthosis Treatment for Mallet Finger Fractures

CONTEXT

Many patients report poor therapeutic outcomes following mallet finger fracture surgery. A more reliable technique is urgently needed.

OBJECTIVE

To present a novel treatment for mallet finger fractures using a 2-step orthosis method.

DESIGN

Prospective, observational study.

SETTING

Hospital.

PARTICIPANTS

Patients with mallet finger fractures.

INTERVENTIONS

The finger is fixed with splints for 6 weeks, including 3 weeks for the proximal interphalangeal joint in the flexion position and the distal interphalangeal joint in the hyperextension position (first splint) and 3 weeks for the distal interphalangeal joint in the hyperextension position (second splint). Up to week 8, the second splint was attached at night and during physical exertion.

MAIN OUTCOME MEASURES

Crawford criteria, Abouna-Brown criteria, bone fusion, grip strength, Doyle classification, Ishiguro classification.

RESULTS

Sufficient bone fusion was achieved 12 weeks after fixation; at which time, the range of motion with the distal interphalangeal joint flexed, and extended in the 3 patients was 50° and 0°, 70° and -3°, and 60° and 0°, respectively. The right and left hand grip strengths in the 3 patients were 58 and 55 kg, 62 and 58 kg, and 31 and 29 kg, respectively; there were no problems with respect to function or work. The first 2 patients could start sports again with partial return after 1 week and complete return after 12 weeks and 8 weeks, respectively. For the third patient, rehabilitation was complete after 16 weeks. Evaluation of the fracture sites based on the Crawford criteria showed the condition to be perfect, and evaluation based on the Abouna-Brown criteria showed success.

CONCLUSIONS

This method provides satisfactory fixation and can prevent proximal interphalangeal joint contracture. Favorable long-term outcomes were confirmed in all patients, suggesting that this method may be effective for previously untreated mallet finger fractures with little displacement.

Hook Plate Technique for Bony Mallet Thumb

Bony mallet is a common sport injury, but bony mallet thumb is rarely encountered. We performed open reduction and fixation of bony mallet thumb using a hook plate procedure on a 27-year-old man under general anesthesia. The patient began working one day after surgery. Six months postoperatively, the patient had excellent dexterity according to Crawford's evaluation criteria and no difficulties at work or playing softball. Tension band fixation, compression pins, and the extension block technique are commonly used to manage bony mallet. Despite the anatomical reduction, rigid fixation, and early resumption of motion skills offered by the hook plate technique, to our knowledge, no previous reports of its application to bony mallet thumb were found. In this case, the hook plate technique was chosen and made an early return to work possible and brought about a successful result.

Supplemental Method for Reduction of Irreducible Mallet Finger Fractures by the 2-Extension Block Technique: The Dorsal Counterforce Technique

PURPOSE

We suggest a method to achieve anatomical reduction in mallet finger fractures that are insufficiently treated by the 2-extension block wire technique.

METHODS

We performed a retrospective review of 18 patients who were found to have an irreducible dorsal fragment and distal interphalangeal joint incongruence owing to rotation of the dorsal fragment in the sagittal plane. In these cases, we additionally employed a dorsal counterforce technique to supplement the 2-extension block technique. An additional K-wire was used to apply counterforce against the distal part of the dorsal fragment and control rotation in the sagittal plane.

RESULTS

All 18 fractures united. Congruent joint surfaces and anatomical reduction were seen in all cases. The mean active flexion of the distal interphalangeal joints was 83.8° (range, 79°-88°) and the mean extension loss was 0.4° (range, 0°-4°).

CONCLUSIONS

We believe that the dorsal counterforce technique effectively supplements the 2-extension block K-wire technique and aids control of dorsal fragment rotation in the sagittal plane.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Outcome of Hook Plate Fixation of Mallet Fractures

BACKGROUND

Hook plate fixation of closed mallet fractures was first described in 2007, but there has subsequently been a lack of studies examining the outcomes and complications of this technique.

METHODS

This paper aims to assess the clinical outcomes of hook plate fixation of closed mallet fractures by retrospectively reviewing 31 closed, bony mallet injuries that were surgically fixed with a hook plate between 2002-2011.

RESULTS

Patients who underwent hook plate fixation had a median time to radiographic union of 83 days. Pre-operative median distal interphalangeal joint (DIPJ) extensor lag was 20°, with a post-operative extensor lag of 0°. Median DIPJ flexion was 60°, with 58% of all cases achieving greater than 50° of DIPJ flexion. There were 4 instances of minor complications (i.e. transient nail deformity and marginal skin flap ischaemia), with 3 cases of major complications (i.e. fracture redisplacement).

CONCLUSIONS

Our results show that the hook plate technique has satisfactory functional outcomes and an acceptable complications rate compared to other treatment modalities in the existing literature. Nevertheless, the outcomes of this technique in our sample population were not as excellent as initially reported.

LEVEL OF EVIDENCE

Level IV: Retrospective case series, Therapeutic Studies.

The Versatile Hook Plate in Avulsion Fractures of the Hand

Avulsion fractures can pose technical difficulties for surgical fixation. The fragments are often small and around finger joints with access being difficult due to attachment of ligaments or tendons. Traditionally, these have been treated using K wires, lag screws, or pullout sutures.Hook plates were originally described for operative management of mallet fractures. We have been using hook plates in our unit for over 10 years. However, over the years, we have extended their use to other avulsion fractures in the hand such as proximal interphalangeal joint fracture dislocations, central slip avulsions, flexor digitorum profundus avulsions and collateral ligament avulsions.The aim of this article is to describe the technique of fabricating a hook plate and using it for avulsion fractures in the hand. A few illustrative cases are discussed along with a review of the current literature.

METHODS

In a retrospective review of our use of hook plates in hand fractures from 2008 to 2014, a total of 63 cases were identified from the hospital data base. There were 35 cases of Mallet fractures, 16 cases of proximal interphalangeal joint fracture dislocations, 5 cases of flexor digitorum profundus avulsion fractures, 5 cases of Central slip avulsions, and 2 collateral ligament avulsions.

RESULTS

All fractures healed well with this technique with no biomechanical failures and good functional outcome. Plates needed removal in a total of 25 cases, of which 14 were in mallet fractures. Thirteen (21%) cases suffered complications, of which the majority were again related to mallet fractures.

CONCLUSIONS

The hook plate is a simple device that can be created quite easily with readily available materials. We have extended the use of these plates to avulsion fracture fixation in the hand and found this to be a versatile technique. The risk of fragmenting the small fracture fragment is reduced because the hooks secure it and the plate is fixed in the bone. If done meticulously, joint congruence can be achieved. It has a biomechanical advantage over current methods of fracture fixation of small but important bone fragments in the hand.

The Outcomes of Extension Block Pinning and Nonsurgical Management for Mallet Fracture

PURPOSE

We aimed to compare the clinical and radiographic results of patients with a mallet fracture involving more than one-third of the articular surface, but without a high degree of distal interphalangeal (DIP) joint subluxation, treated with extension block pinning or nonsurgical management.

METHODS

Forty-nine patients with a mallet fracture involving more than one-third of the articular surface were reviewed. Twenty-six cases were treated using extension block pinning (surgery group) and 23 were treated nonsurgically (nonsurgical group). At the final follow-up, extension lag and flexion of the DIP joint of the affected digit were measured. Distal interphalangeal joint pain was rated using a visual analog scale and the overall clinical outcomes were graded using Crawford's criteria. Complications, including nail deformity and dorsal prominence, were also assessed. The rate of DIP joint subluxation and fracture fragment size were radiographically evaluated.

RESULTS

Mean extension lag and flexion of the DIP joint and mean visual analog pain scores were not significantly different in the 2 groups. Outcomes, as assessed using Crawford's criteria, were excellent in 5, good in 12, fair in 6, and poor in 3 in the surgery group, and excellent in 2, good in 11, fair in 8, and poor in 2 in the nonsurgical group. Moreover, the frequency of nail deformity or dorsal prominence was similar in the 2 groups. The rate of DIP subluxation and mean fracture fragment size were similar between the 2 groups. All the fractures had united by 3 months after injury in both groups.

CONCLUSIONS

The clinical outcomes do not significantly differ between extension block pinning and nonsurgical management for mallet fractures involving more than one-third of the articular surface, but without high degree subluxation of the DIP joint.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Tips and Tricks in Mallet Fracture Fixation

We describe three steps to aid fracture assessment and fixation in the extensor block pin technique for mallet fractures. The first step is the use of fluoroscopy in the initial assessment to determine indication for fixation. Next is the use of supplementary extension block pin to control larger dorsal fragments. The third technique described details the steps of open reduction of nascently malunited fractures.

Clinical comparison of hook plate fixation versus extension block pinning for bony mallet finger: a retrospective comparison study

The aim of this retrospective study was to determine whether traumatic mallet fractures had better outcomes when treated by hook plate fixation (13 patients) or extension block pinning (19 patients). We assessed outcomes using Crawford's criteria; distal interphalangeal joint range of motion; the DASH score; and a visual analogue scale score for pain. We measured radiological parameters. No significant differences were observed in functional and clinical outcomes and in complications. Whereas the operative time was longer in the hook plate group, intraoperative fluoroscopy use, time to bone union and time to return to work were greater in the extension block group. Although the hook plate method is more technically demanding, it provides good stable reduction, earlier mobilization and an earlier return to work. The extension block pinning technique is easier and as effective but it requires greater peri-operative fluoroscopy. Level of evidence: Level III.

Extension Block Pinning Versus Hook Plate Fixation for Treatment of Mallet Fractures

PURPOSE

To compare the outcomes and associated costs of the treatment of mallet fractures with either extension block pinning or open reduction and hook plate fixation.

METHODS

We treated 22 patients for a mallet fracture that involved at least 25% of the distal phalanx articular surface. Three joints demonstrated concomitant volar subluxation. Extension block pinning was used to treat 16 fractures (group 1) and 6 were treated with open reduction and hook plate fixation (group 2). All patients were evaluated at the second, fourth, and sixth weeks after surgery. Collected data included range of motion, extensor lag, and pain status. Patients were asked to grade preoperative and postoperative pain levels on a visual analog scale. Functional outcomes were determined by Crawford criteria. We retrospectively performed a cost analysis using our institutional records.

RESULTS

Mean follow-up was 12.7 months. Visual analog scale pain scores improved by a similar amount for both groups. Preoperative pain scores were 7.0 for group 1 and 7.5 for group 2. Postoperative levels were 2.0 and 2.0, respectively. Mean extensor lag was identical for both groups, 5°. Mean flexion was 70° for group 1 and 80° for group 2. Based on the Crawford criteria, group 1 had 5 patients rated as excellent, 6 as good, 3 as fair, and 2 as poor. Group 2 outcomes were 2 excellent, 2 good, and 2 fair. Five complications occurred in group 1, and 1 in group 2. Differences noted between groups were not statistically significant. Extension block pinning was more cost-effective than hook plate fixation.

CONCLUSIONS

We find extension block pinning to be an equally effective but more cost-efficient treatment than open reduction and hook plate fixation.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic III.

[Treatment of phalangeal fractures using the mini-hook plate. An alternative for surgical fixation of small phalangeal bone fragments?]

BACKGROUND

Fixation of the small bony fragments of the phalanges is often difficult. In this study a clinical and radiological evaluation was carried out after operative treatment using the mini-hook plate.

PATIENTS AND METHODS

Between 2003 and 2006 a total of 36 fractures were treated operatively using the mini-hook plate. Of the patients 24 had an basal avulsion fracture of the distal phalanx and 11 patients (12 fractures) had other bony avulsion fractures of the phalanges. The patients were evaluated clinically and radiologically as well as using the disabilities of the arm, shoulder and hand (DASH) questionnaire.

RESULTS

A total of 29 patients with 30 fractures were examined. The mean follow-up was 13.6 months. The mean range of motion in the affected finger joint was 60.3 ° and the mean DASH score was 2.8 points. Postoperatively five nail growth defects, one infection and one secondary dislocation of the implant were observed.

CONCLUSION

Using the mini-hook plate, preservation of the joint and stable internal fixation with no need for temporary arthrodesis is possible; however, prerequisites are experience and skill of the surgeon with a difficult surgical technique.

The Meniscus Arrow® as a fixation device for the treatment of mallet fractures: results of 50 cases

BACKGROUND

The treatment of mallet fractures is a controversial and challenging problem. Generally, mallet fractures are treated conservatively except those involving more than one third of the base of the distal phalanx. Many different surgical fixation techniques have been published. This paper describes a new fixation procedure using ultimate bioresorbable meniscal fixation nails (Meniscus Arrows®).

METHODS

Mallet fractures in 50 digits of 49 patients were fixed with this nail in an outpatient surgical procedure, mostly under local (Oberst-block) anaesthesia. The average operation time was 21 min.

RESULTS

According to the Crawford criteria, patient outcome was graded as excellent in 48 %, good in 22 %, and fair in 28 %. In one patient, the outcome was graded as poor, but the fracture was in a pre-existent arthritic joint. All fractures were consolidated without recurrent dislocation. Complications included one wound infection, which was successfully treated with antibiotics and without further consequences. No nail deformities occurred. Two times, the nail spontaneously and gradually dislocated during intensive use of the hand after, respectively, 3 and 6 months and could easily be removed under local anaesthesia without any functional sequelae.

CONCLUSION

The bioresorbable meniscal nail fixation technique provides a fast and successful surgical treatment for mallet fractures with a minimum of adverse events.

Current concepts: mallet finger

Loss of the extensor mechanism at the distal interphalangeal (DIP) joint leads to mallet finger also known as baseball finger or drop finger. This can be secondary to tendon substance disruption or to a bony avulsion. Soft tissue mallet finger is the result of a rupture of the extensor tendon in Zone 1, and a bony mallet finger is the result of an avulsion of the extensor tendon from the distal phalanx with a small fragment of bone attached to the avulsed tendon. Mallet finger leads to an imbalance in the distribution of the extensor force between the proximal interphalangeal (PIP) and DIP joints. If left untreated, mallet finger leads to a swan neck deformity from PIP joint hyper extension and DIP joint flexion. Most mallet finger injuries can be managed non-surgically, but occasionally surgery is recommended for either an acute or a chronic mallet finger or for salvage of failed prior treatment.

Peak load resistance of the JuggerKnot™ soft anchor technique compared with other common fixation techniques for large mallet finger fractures

INTRODUCTION

To identify the strongest peak load resistance among four mallet finger fracture fixation methods (Kirschner wire, pull-out wire, tension-band wiring and the JuggerKnot™ (Biomet) soft anchor fixation).

METHODS

Fixation techniques were assigned among 24 specimens from six cadaveric human hands in a randomized block fashion. Peak load resistance was tested at 30°, 45° and 60° of flexion of the distal interphalangeal joint.

RESULTS

The mean peak load of tension-band wiring was 67.8 N at 60° of flexion which was most superior. The JuggerKnot™ fixation had mean peak loads of 13.35 N (30°), 22.51 N (45°) and 32.96 N (60°). No complications of implant failure or fragmentation of the dorsal fragment was noted.

CONCLUSIONS

Tension-band wiring was the strongest fixation method but was most prominent on the skin surface as seen in three specimens. The JuggerKnot™ soft anchor fixation had similar peak load resistance as k-wire fixation and pull-out wiring.

REVIEW ON MALLET FINGER TREATMENT

Mallet finger is a common injury involving either an extensor tendon rupture at its insertion or an avulsion fracture involving the insertion of the terminal extensor tendon. It is usually caused by a forceful blow to the tip of the finger causing sudden flexion or a hyperextension injury. Fracture at the dorsal aspect of the base of the distal phalanx is commonly associated with palmar subluxation of the distal phalanx. Most mallet finger injuries are recommended to be treated with immobilisation of the distal interphalangeal joint in extension by splints. There is no consensus on the type of splint and the duration of use. Most studies have shown comparable results with different splints. Surgical fixation is still indicated in certain conditions such as open injuries, avulsion fracture involving at least one third of the articular surface with or without palmar subluxation of the distal phalanx and also failed splinting treatment.

[Operative treatment of osseous pull out of the extensor tendon using a hook plate]

OBJECTIVE

Anatomical reposition and stabilization of dorsal distal phalanx fractures with a hook plate.

INDICATIONS

Dislocated mallet fractures type Doyle IVb with dislocation of the fragment by more than 2 mm and/or tilting of the fragment as well as dislocation of the dorsal distal phalanx fractures type Doyle IVc.

CONTRAINDICATIONS

Florid inflammation of and injuries to the soft tissues in the operation area.

SURGICAL TECHNIQUE

Dorsal approach to the distal interphalangeal joint (Y-, S-, H-shaped). Preparation of the fragment, cleaning the fracture gap, repositioning of the fragment, mounting of the plate, placing the screw. Controlling by image converter. Suture of the skin; tape.

POSTOPERATIVE MANAGEMENT

Stack splint for 4 weeks. After week 3, start with exercising of the distal interphalangeal joint within the splint. Physiotherapy is usually not required. Full exertion after 6-8 weeks is possible. The period of inability to work is dependent on the patient's occupation. Due to the danger of perforation and infection, it is recommended that the plate be removed after 3-6 months.

RESULTS

From February 2002 to September 2009, 77 mallet fractures type Doyle IVb and IVc were operatively stabilized with a hook plate. In a retrospective study, 59 patients were followed up at a mean interval of 38.3 (3-69) months after the operation. Wound healing problems or inflammation were not observed. Visible disturbances of nail growth were macroscopically seen in 11.9%. Results were very good in 35 patients (59.3%), good in 16 patients (27.1%), sufficient in 5 patients (8.5%), satisfying in 1 patient (1.7%), and insufficient in 2 patients (3.4%).

Mini hook plate fixation for palmar fracture-dislocation of the proximal interphalangeal joint

Fracture-dislocations of the proximal interphalangeal joint are challenging to treat, since it is difficult to achieve both rigid fixation and early joint motion simultaneously. Palmar fracture-dislocations of the proximal interphalangeal joint are less frequent injuries and a small number of treatment methods have been reported. We describe here a patient with a chronic palmar fracture-dislocation of the proximal interphalangeal joint, who was treated with a new surgical technique. In the surgery, a mini hook plate that was made by adapting a 1.5 mm AO hand modular system straight plate was used. Despite the thinness of the fragment, rigid fixation was achieved, resulting in early active motion. At final follow up, the active ranges of motion were 0°-100° at the proximal and 0°-80° at the distal interphalangeal joint, and there were no complications. This technique may become a useful surgical method to treat palmar fracture-dislocations of the proximal interphalangeal joint.

Pull-out wire fixation for acute mallet finger fractures with k-wire stabilization of the distal interphalangeal joint

PURPOSE

The aim of this study was to describe and assess a surgical technique for the treatment of mallet finger fractures using a pull-out wire with K-wire stabilization of the distal interphalangeal (DIP) joint in extension.

METHODS

From May 2003 to January 2008, we performed pull-out wire fixation of the fracture fragment with stabilization of the DIP joint using a K-wire in 65 closed mallet finger fractures in 65 patients with a mean age of 32 years (range, 18-48). The mean time between the injury and surgery was 8 days (range, 0-19 d). In this cohort, the mean joint surface involvement was 39% (range, 30% to 49%) and all injuries were associated with DIP joint subluxation. Fifteen days after surgery, the digits were assessed for skin necrosis, skin breakdown, and wound and wire track infection. Patient follow-up lasted 24 to 27 months, with a mean period of 25.5 months. The fingers were assessed for loss of extension and flexion of the DIP joints. We graded the results using Crawford's criteria.

RESULTS

Fracture reduction was maintained and all fractures united. We found no skin necrosis, skin breakdown, infection, or nail deformities. At the final follow-up, the mean extensor loss of the DIP joints was 7° (range, 0° to 37°). The mean flexion loss of the DIP joints was 1° (range, 0° to 15°). We noted extensor loss of the joint less than 10° in 57 digits and 10° to 15° (mean, 13°) in 8 digits. Based on Crawford's criteria, 52 digits were excellent, 8 were good, 4 were fair, and one was poor.

CONCLUSIONS

Pull-out wire fixation of the reduced fracture fragment and K-wire stabilization of the DIP joint is a useful technique for the treatment of mallet finger fractures.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Modified extension-block K-wire fixation technique for the treatment of bony mallet finger

This article describes the treatment of a bony mallet finger deformity using 2 extension-block Kirschner wires (K-wires) with a transarticular K-wire fixation technique for precise alignment of the terminal extensor tendon-bone relationship and effective immobilization of the distal interphalangeal joint. Twenty-nine patients (33 fingers) with a bony mallet finger deformity and fracture fragment involving more than one-third of the articular surface were treated surgically. The fracture fragment was fixed and the mallet finger deformity was corrected in all patients using modified extension-block K-wires (2 dorsal extension-block pins) with a transarticular K-wire (volar side pin) fixation technique. Active motion of the proximal interphalangeal and metacarpophalangeal joints was not restricted. The wires are removed in the clinic 6 weeks postoperatively when the bridging trabeculae were observed in the radiographs, and immobilization in a stock splint was continued for an additional 2 weeks. According to Crawford's evaluation criteria, there were 24 (73%) excellent, 7 (21%) good, and 2 (6%) fair results. Three patients showed radiological signs of mild degenerative changes, which did not limit their daily activities. Nail ridging occurred in 3 cases (9%), which disappeared after an average of 6 months with normal growth, and mild scarring at the dorsal pin site occurred in 2 cases (6%). Modified extension-block K-wires with a transarticular K-wire fixation technique is an acceptable alternative treatment modality for the management of bony mallet finger deformities with or without subluxation of the distal phalanx.